Spinach & Mushroom Quiche

This healthy vegetarian quiche recipe is as simple as it gets. This is quiche without the fussy crust! It is full of sweet wild mushrooms and spicy Gruyère cheese. Enjoy it for breakfast or brunch or serve it with a light salad for lunch.

2 tablespoons extra virgin olive oil

8 ounces sliced ​​fresh mixed wild mushrooms such as flint, shiitake, buttons and / or oysters

1 ½ cups thinly sliced ​​sweet onion

1 tablespoon finely chopped garlic

5 ounces fresh baby spinach (about 8 cups), chopped in bulk

6 large eggs

¼ A glass of whole milk

¼ half a cup

1 tablespoon Dijon mustard

1 tablespoon fresh thyme leaves, plus more for garnish

¼ teaspoon of salt

¼ teaspoon ground pepper

1 ½ cup grated Gruyère cheese