Pre heat the oven at 180 degC.
Unroll the Pâte Brisée on the mold and perforate the bottom with a fork.
Cover the bottom with Dijon mustard
Add the grated cheese
Add a first layer of tomato, add the onion rings. Finally add a second layer of tomato slices, covering the onion rings.
Drizzle with olive oil, add a pinch of salt and black pepper
Sprinkle with fresh thyme.
Bake for 20 - 30 min @ 180 degC. Until the Pâte Brisée is golden brown and the tomatoes are cook.