Superfood Siobhan

Healthy Plant Based recipes that make you look and feel great

Tomato and Dijon Mustard Tart

By Wednesday, July 30, 2014 , , , ,

My Mum first made this delicious summer dish back in about 2009 when we were visiting my aunt in France. I loved the combination of the creaminess and the spiciness of the mustard combined with the juicy tomato. It's so simple and tasty and with a little manipulation of the pastry recipe, very easily gluten free and vegan!

Gluten free pastry is a nightmare and I have never been able to make a decent one. That is until my mother and I discovered a recipe in an Irish cookbook for an apple pie where you put mashed potato in the pastry. Sounds bizarre, right? Some internet research later we discovered that this genuinely is used by people and it yields fantastic results! The mashed potato makes it a lot more moist and easy to roll out, so you get a perfect result. Plus the pastry gets lovely and brown and crispy too!

Makes 1 medium sized tart

You will need:

30g brown rice flour
20g cornmeal powder (you can put polenta in the food processor for this)
1 tsp baking powder
1/2 tsp xanthan gum
100g of cold white potato, mashed until smooth
80g vegan 'butter' such as Trex vegetable oil spread (it needs to be a solid fat for making pastry)

2 large tomatoes, sliced thinly
1 1/2-2 tbsps dijon mustard
Salt and pepper

Add the flour, baking powder, xanthan gum and cornmeal powder into a large bowl. Using your fingers, rub the vegan butter into the flour mixture until it makes a breadcrumby consistency. Mix in the mashed potato using your hands, roll into a ball and chill wrapped in cling wrap for 30 minutes. Remove from fridge, knead a little and place in the fridge to cool uncovered on a plate for another 30 minutes.

Preheat your oven to 180C. Flour your bench top and rolling pin well and gently roll out the pastry out so it is flat but still quite thick. Don't worry about making it neat or the exact size of the tin, as you can press the pastry into the tart tin to make it fit perfectly and have a nice crust.

Spread the dijon mustard over the base, then layer your slices of tomato. Sprinkle with salt and pepper and bake for about 30 minutes, turning the tin around halfway to ensure it bakes evenly.

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  1. Would coconut oil work instead of vegan butter?

    1. I'm not actually sure if it works to use coconut oil for pastry! Perhaps a little research into this is needed first?

  2. Could I use soaked chia seeds instead of xanthan gum?

    1. I don't so, they're completely different textures. The xantham gum stops it from being so crumbly, it's not essential though

  3. This sounds delicious, I'm trying it tomorrow but I have a question: Is this better eaten while warm or does it also work cold? Thanks, darling, I really love your recipes!