This is such a gorgeous summer dish celebrating the delicious flavours of seasonal tomatoes and courgettes. Inspired by a traditional French gratin, this Courgette Gratin (Gratin de Courgettes in France) is my go-to easy entertaining recipe served with a selection of summer salads and some hot crusty bread. It looks so impressive but, like so many of my recipes, doesn’t take too much effort and relies on the oven to do the hard work.
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This perhaps isn't a gratin in the traditional sense which may be creamier and more hearty, this is almost a summer twist on it and paired with juicy tomatoes for something bright and delicious. The whipped Boursin on top takes it to the next level but it's really simple to mix together. I love drizzling fresh pesto over the courgettes, as I find it ties together really nicely with the other flavours.
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Why you will love this recipe:
- The perfect summer recipe to use up a glut of courgettes and make the most of seasonal tomatoes.
- Ideal for entertaining as it looks so impressive but is actually very simple - plus it can be prepped ahead.
- A delicious and interesting way to serve vegetables.
- It is suitable for vegetarians (make sure your pesto doesn’t contain Parmesan) and can be adapted for vegans.
A note on the serving size:
I always find it a bit tricky to say how many people my recipes serve as I like to have (and serve) generous portions (Nigella and I are kindred spirits on that front). This Gratin de Courgettes would serve 4 people generously, or 6 people who prefer smaller portions.
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Ingredients:
See recipe card at the bottom of the page for a full list of ingredients and measurements.
Cherry tomatoes - plump and juicy seasonal cherry tomatoes make the most delicious homemade tomato sauce. You could use baby plum tomatoes instead.
Garlic cloves - you don’t need much garlic in the tomato sauce as there is garlic in the Boursin and the pesto garnish. You could substitute for garlic granules if you have run out of fresh.
Basil - adding some leaves to the tomato sauce adds a lovely basil flavour throughout the dish. The basil leaves look beautiful as a garnish on top too.
Garlic and Herb Boursin - this soft and creamy French cheese that takes this Courgette Gratin (Gratin de Courgettes) to the next level. Its signature flavour works beautifully with the vegetables.
Courgettes - I like to use a variety of different colours from dark green to striped to bright yellow. The latter taste slightly sweeter and are absolutely delicious. You could use all regular courgettes if you prefer.
Thyme - I like to use freshly plucked thyme but you could use a generous pinch of dried thyme or herbes de provence if you can’t get hold of fresh.
Plum tomatoes - opt for ripe, plump and juicy tomatoes and cut thinly using a sharp knife.
Double cream - also known as heavy cream. You need the higher fat content to get the right texture so don’t be tempted to use single cream.
Fresh pesto - either homemade or shop bought. If using the latter, I like to buy the pot in the chilled section, it is a world away from the jarred version.
Substitutions and Variations
Boursin: I think the Boursin really makes this dish so I recommend trying to find some if you can. If you can’t get hold of any, try with a soft goat's cheese or feta whipped up with the cream. You could add some garlic granules and fresh herbs to mimic the garlic/herb flavour in Boursin. Alternatively, you could just leave it out.
Cherry tomatoes: I love using cherry tomatoes here in the sauce but you could use baby plum tomatoes instead. Or use large tomatoes chopped up for the base sauce, since you are already using large tomatoes in slices. Tinned tomatoes would also work if you had those to hand for the sauce but keep the fresh large tomatoes for the slices in the gratin.
Thyme: If you can't find thyme or don't like it, dried herbs de Provence is a good choice or fresh rosemary works too! Fresh basil is also a delicious option.
Here's how to make a delicious Gratin de Courgettes:
Here's a step by step guide for what you need to do, but you can find the full recipe at the bottom of the page for detailed instructions.
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ONE: Using a mandoline, thinly slice the courgettes. See my Cooking Tips above for advice on this.
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TWO: Tip into a large mixing bowl and drizzle generously with olive oil, then season with salt and freshly ground black pepper. Sprinkle in the freshly plucked thyme leaves from the sprigs. Use your hands to coat the slices with the oil and seasoning.
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THREE: Using a sharp knife, thinly slice the tomatoes, place into a bowl and season with salt and freshly ground black pepper.
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FOUR: Make the tomato sauce: heat the olive oil, add the cherry tomatoes, season well and cook for 3 minutes or until the tomatoes start to burst. Add the sliced garlic and cook for another 30 seconds, stirring occasionally. Tip into the serving dish.
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FIVE: Sprinkle the sauce with basil then start layering. Carefully arrange 2 rows of courgette slices. Spread some of the Garlic and Herb Boursin onto the tomato slices before adding a neat row next to the courgette.
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SIX: Repeat, alternating between 2 rows of courgette, followed by 1 row of Garlic and Herb Boursin-spread tomato, until you have filled your dish.
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SEVEN: Drizzle with olive oil and season with salt and freshly ground black pepper. Bake for about 35 minutes or until softened and golden.
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EIGHT: Meanwhile, make the whipped Boursin: place the Boursin and double cream into a foot processor and blitz for about 1 minute.
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NINE: It should be smooth and creamy like this. Transfer to a small bowl.
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TEN: Once the courgette gratin is cooked, remove from the oven and garnish with a few dollops of the whipped boursin, some fresh basil leaves and a drizzle of fresh pesto.
Cooking Tips
Using a mandolin: I love my mandolin - it is one of my favourite kitchen gadgets as it makes slicing vegetables thinly unbelievably quick and easy. However, they are very sharp and, if not used correctly, can be dangerous. Always make sure what you are cutting has a flat surface and wear a hand guard at all times. If you prefer not to use a mandolin, slice very thinly using a sharp knife or use the slicing attachment on your food processor.
Assembly: If you aren't that particular about the layering and the look, then don't worry too much and just make sure that the Boursin is nicely spread between veggies and then it will still roast nicely all together.
Frequently Asked Questions
A gratin is normally any dish that is topped with cheese and/or breadcrumbs and baked (or grilled) until golden brown and crisp. Pommes au Gratin is probably the most famous version. This Courgette Gratin is my more modern, lighter twist on the classic which is perfect for the summer months.
Boursin is a soft and creamy flavoured French cheese - a bit similar in texture to cream cheese. Garlic and Herb is the classic option but there are now quite a few different flavours. It is delicious used in so many ways… on toast, in sandwiches, quiches and tarts, or in pasta dishes (like my Boursin Tomato Pasta).
This is the perfect entertaining recipe to serve with a selection of your favourite summer salads like roasted peppers, couscous, beetroot salad etc. or for a simple summer supper with some hot crusty bread, butter and a crisp mixed salad.
Yes, simply leave the dish to cool completely before covering and chilling in the fridge for up to 3 days. It reheats well in the oven. You can also keep any leftover whipped Boursin - it is delicious on bruschetta or stirred through pasta.
You could arrange the dish pre baking. Cover and chill up to a day in advance then bake when you are ready to eat. The Boursin cream can be made 2 days in advance and stored in the fridge in an airtight container.
I wouldn't recommend freezing this recipe as neither the Boursin nor the raw veggies freeze very well.
Other recipes you may enjoy:
This is another boursin favourite of mine, it's Boursin Tomato Pasta and a really simple delicious pasta. I also love courgettes in other recipes, you should try my Easy Courgette Lasagne if you do too. I love to garnish this gratin with some pesto drizzled over the top. If you want to make your own, this Pasta al Pesto recipe post has all the details.
Made this recipe and loved it?
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PrintCourgette Gratin (Gratin de Courgettes)
This gorgeous gratin is bursting with the flavours of sweet tomatoes, courgettes and fresh basil. A true celebration of summer...
- Prep Time: 15 minutes
- Cook Time: 45 minutes
- Total Time: 60 minutes
- Yield: Serves 6
- Category: Adaptable for Vegetarians, Adaptable for Vegans
- Method: Oven
- Cuisine: French
- Diet: Vegetarian
Ingredients
For the gratin:
- 2 tbsp olive oil, plus extra for drizzling
- 400g cherry tomatoes
- Salt and freshly ground black pepper
- 2 cloves garlic, finely sliced
- ½ bunch of basil, finely sliced
- 8 courgettes, a variety of colours ideally but any will work
- 3 sprigs of fresh thyme
- 6 large ripe tomatoes
- 150g Garlic and Herb Boursin, at room temperature
For the whipped Boursin:
- 150g Garlic and Herb Boursin
- 100ml double cream
To garnish:
- Fresh basil leaves
- 2 tbsp fresh pesto
To serve:
- Hot crusty bread
- Fresh green salad
Instructions
- Preheat the oven to 180C Fan. Set out an oven-proof serving dish - I use a 25.5cm (10-inch) pie dish but you could use a roasting tin or any other similar-sized dish with high-ish sides.
- Make the tomato sauce: heat the olive oil in a large non-stick frying pan over a medium-high heat. Once hot, add the cherry tomatoes, season well and cook for 3 minutes or until the tomatoes start to burst. Using the back of a wooden spoon, break them down to form a sauce. Add the sliced garlic and cook for another 30 seconds, stirring occasionally.
- Tip into your serving dish and sprinkle with the sliced basil. Set aside.
- Using a mandoline, thinly slice the courgettes. Tip into a large mixing bowl and drizzle generously with olive oil, then season with salt and freshly ground black pepper. Sprinkle in the freshly plucked thyme leaves from the sprigs. Use your hands to coat the slices with the oil and seasoning.
- Using a sharp knife, thinly slice the tomatoes, place into a bowl and season with salt and freshly ground black pepper.
- To assemble, carefully arrange 2 rows of courgette slices. Spread some of the Garlic and Herb Boursin onto the tomato slices before adding a neat row next to the courgette. Repeat, alternating between 2 rows of courgette, followed by 1 row of Garlic and Herb Boursin-spread tomato, until you have filled your dish.
- Drizzle with olive oil and season with salt and freshly ground black pepper. Bake for about 35 minutes or until softened and golden.
- Meanwhile, make the whipped Boursin: place the Boursin and double cream into a food processor and blitz for about 1 minute - or until smooth and creamy. Spoon into a bowl.
- Once the gratin is cooked, remove from the oven and garnish with a few dollops of the whipped boursin, some fresh basil leaves and a drizzle of fresh pesto.
- Serve with hot crusty bread, the remaining whipped boursin and a fresh green salad. Enjoy!
Notes
Scroll up for a simple step by step guide with images to help you make this gratin.
To store: Yes, simply leave the dish to cool completely before covering and chilling in the fridge for up to 3 days. It reheats well in the oven. You can also keep any leftover whipped Boursin - it is delicious on bruschetta or stirred through pasta.
To reheat: Reheat in the oven at 170c for 5-10 minutes until hot all the way through. Or heat in the microwave for 1-2 minutes until hot.
To freeze: I wouldn't recommend freezing this recipe as neither the Boursin nor the raw veggies freeze very well.
Make ahead: You could arrange the dish pre baking. Cover and chill up to a day in advance then bake when you are ready to eat. The Boursin cream can be made 2 days in advance and stored in the fridge in an airtight container.
Mandolin safety: When using a mandolin, always follow the relevant safety procedures. Make sure what you are cutting has a flat surface and wear a hand guard at all times. If you prefer not to use a mandolin, slice very thinly using a sharp knife or use the slicing attachment on your food processor.
Vegetarian friendly: If making this dish for vegetarians make sure your pesto doesn’t contain Parmesan.
Make it plant based: You can make this recipe suitable for vegans by using Boursin Plant-Based, a vegan-friendly double cream and making your own fresh vegan pesto. You could make it without the Boursin and whipped Boursin, if you like.
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