Preheat your oven to 350°F (175°C).

Combine flour and salt in a bowl. In a separate bowl, whisk together oil and cold water, then mix into the flour until the dough comes together.

Divide the dough into four portions. Roll each portion thin and press them into mini tart pans.

Sauté chopped mushrooms and diced onion over medium heat for about 5-7 minutes until golden.

Add minced garlic in the last minute.

Whisk together eggs and cream until smooth.

Layer the sautéed mushrooms, onions, and Swiss cheese in each crust.

Pour the egg mixture in until each is about 3/4 full.

Bake for 30-35 minutes until the edges are golden brown and the filling is set.

Cool the quiches for a few minutes before serving.