This is not your ordinary quiche. What I like best about it is the combination of earthy baby Portobello mushrooms (Cremini) and nutty Gruyère cheese. Carefully layering the mushrooms and shredded Gruyère ensures consistently good flavor throughout.
I like to take this to pot luck gatherings where it is always a hit. If paired with slightly chilled* Pinot Noir and a fresh garden salad, it is a complete and nutritious late lunch or early dinner.
¾ cup whole-wheat pastry flour
¼ cup all purpose flour
¼ cup whole ground flaxseed meal
⅛ teaspoon salt
2 tablespoons butter
2 tablespoons organic vegetable oil
5 tablespoons ice water
1 teaspoon olive oil
16 ounces Cremini mushrooms (sliced thickly)
1 small onion (chopped)
3 cloves garlic (minced)
1 tablespoon fresh thyme (chopped fine)
2 large eggs
3 egg whites
1 ½ cups milk (I use whole milk)
2 teaspoons Dijon mustard
¼ teaspoon grated fresh nutmeg
1 cup grated Gruyère cheese
Salt and pepper to taste
Crust: Preheat oven to 425 degrees.
Whisk flours, flaxseed meal and salt together in a large bowl.
Heat butter in small skillet over low heat; cook until butter turns deep golden brown. Stir browned butter and oil into flour mixture with fork. Gradually stir in ice water until dough forms an easy-to-handle ball. Roll ball into 12-inch circle, then press dough into a 9-inch spring form pan. Crimp dough at edges, and prick sides and bottom all over with fork. Pre-bake for 10 minutes at 425 degrees. Remove from oven to cool and reduce oven to 350 degrees.
Filling: Heat oil in large skillet over medium-high heat. Add mushrooms and onion; sauté 8 minutes, or until browned and mushroom liquid has evaporated. Stir in garlic and thyme.
Whisk together eggs and egg whites in bowl. Whisk in milk, mustard, and nutmeg. Season with salt and pepper to taste.
Assembly: Sprinkle half of grated cheese on pre-baked crust. Top with mushroom mixture, then remaining cheese. Pour egg mixture over the top making sure mushrooms remain well-distributed in crust.
Bake completed quiche at 350 degrees for one hour or until firm. Let cool for about 10 minutes before serving.
* by slightly chilled I mean 15 to 20 minutes in the refrigerator, no more.