1. Pour the flour, butter, salt and sugar in a mixer bowl and blend at high speed until you get a sandy texture.

2. Add the egg and milk, and mix in spurts until the dough pulls away from sides of bowl and forms a ball.

3. Lightly flour the dough ball and put at least 30 minutes and ideally fresh 3 hours.

4. Turn the oven on 180°C, butter a pie pan. Roll out the dough on the floured surface, put it into the mold and prick several times with the fork.

5. Spread mustard on the dough. Cut the tomatoes into slices, arrange on the pastry, salt and pepper and bake 20 minutes. Add cherry tomatoes and thyme and cook around 20 minutes.