This tomato tart with mustard shallots is everything I love about cooking with seasonal produce at its very best and evokes memories of living in France. A buttery, mustard-flecked shortcrust pastry case, a layer of Dijon mustard and sweet, garlicky shallots. Then those beautiful tomatoes – sliced thinly and arranged in concentric circles, their red and yellow colours almost too pretty to eat. Almost.
Make lunchtime special
This tomato tart with mustard shallots is the kind of lunch that feels really special, and yet it’s far more straightforward to make than it looks. Perfect for a lazy weekend lunch with a glass of something cold, or to take along to a summer gathering where you want to impress without spending all day in the kitchen.
Why this tomato tart works so well
The secret to this tart is in the layers of flavour built up before the tomatoes even go on. The pastry itself has mustard powder worked into it, which gives it a subtle warmth and a beautiful savoury depth. Then the base is spread generously with Dijon mustard before the shallots go on – and those shallots, softened slowly in olive oil with garlic and thyme, are absolutely worth the extra few minutes they take.
Once topped with the tomatoes and baked, the tomatoes soften and concentrate. Then we add the cheese, which melts and adds a golden, slightly salty crust, and the fresh thyme on top makes the whole kitchen smell incredible.
Choosing your tomatoes
You want bang in-season ripe tomatoes for this recipe. We’re not adding any egg or cream to the filling, therefore we need some juicy tomatoes to create that beautifully sweet filling. I love using a mix of varieties of red and yellow tomatoes. The combination of colours makes the tart look absolutely stunning, and the slightly different flavour profiles of each variety add to the overall depth of the dish.
Other similar recipes
Below you will find some other lunchtime and tomato recipes from the blog:
- Squid, chorizo and tomatoes on toast
- Fresh tomato and oregano fritters with yoghurt
- Simple cheese and tomato tart
- Creamy roasted cherry tomato risotto
Totally. You’ll loose a slight hint of mustard that you add in when you make it yourself. But with the nice layer of Dijon mustard that is spread on the cooked pastry case, it will still shine through.
Yes — this tart is actually great made a few hours ahead and served at room temperature. Once baked and cooled, keep it loosely covered at room temperature for up to a few hours, or in the fridge for up to a day. Allow it to come back to room temperature before serving for the best flavour.
The dried thyme goes into the shallot mixture during cooking, which is already in the recipe. The fresh thyme leaves scattered on top at the end are worth using if you can – they add a lovely brightness and look beautiful. But if you only have dried, a small pinch scattered over at the end will still work.
Yes. This is an important step and one that’s well worth doing. Blind baking the pastry case first ensures you end up with a crisp, golden base rather than a soggy one. It only takes 30 minutes in total, and the result is really worth it.
Tomato Tart with Mustard Shallots
Equipment
- 23cm round loose-bottomed tin
- baking beans or similar
Ingredients
- 240 g plain flour
- 1 tsp salt
- 1/2 tsp mustard powder
- 120 g butter cold and cubed
- 1 tbsp extra virgin olive oil
- 2 shallots finely sliced
- 2 garlic cloves grated
- 400 g tomatoes sliced relatively thinly – a mix of colours is nice
- 1 tsp dried thyme
- 2 tbsp Dijon mustard
- 15 g parmesan finely grated
- 35 g cheddar cheese grated
- 1 tbsp fresh thyme leaves
Instructions
- To make the pastry, add the flour, salt and mustard powder to a large bowl and stir. Add the cold butter and rub with your fingertips until you have a breadcrumb consistency. Mix in 4 tablespoons of cold water and start to bring the dough together. Add a tablespoon more of cold water at a time until you can shape the dough into a ball. Cover and pop in the fridge for 30 minutes.
- Preheat the oven to 180 °C
- Remove the pastry from the fridge and roll it out to fit the tin. Once your pastry is in the tin, slightly overlapping the sides, line it with baking paper and add the baking beans or equivalent.
- Blind bake the pastry case in the middle of the oven for 20 minutes. Remove and carefully lift up the paper along with the beans, and return to the oven for 10 minutes.
- Now heat the tablespoon of oil in a fry pan and gently fry the sliced shallots for 6 minutes. Add in the grated garlic and cook for a further 2 minutes. Stir in the teaspoon of dried thyme.
- Remove the tart from the oven after 30 minutes. Spread the base with the Dijon mustard, then layer in the shallots and finally arrange the sliced tomatoes on top.
- Bake in the oven for 30 minutes. Remove the tart, sprinkle on the cheddar cheese, the grated parmesan, and finally top with the fresh thyme leaves. Return to the oven for a final 10 minutes.
- Remove from the oven and allow the tart to rest for 5 minutes before slicing and serving along with a green side salad.
Notes
- You can, of course, buy ready-made shortcrust pastry and bypass making your own.