Vegetarian Quiche Recipe

Make dough

In a medium bowl, whisk together 1.25 cups flour and 0.5 tsp salt. Cut 6 tbs cold unsalted butter into small cubes and use a pastry cutter or fingertips to work butter into flour until mixture resembles coarse crumbs with some pea-sized pieces (about 6-8 strokes).

Add water and chill

Drizzle 3 tbs ice water over the mixture, stirring gently with a fork until dough just comes together. If dry, add up to 1 tbs more water. Form dough into a disk, wrap in plastic, and chill in refrigerator for at least 30 minutes (up to 2 days).

Roll and blind-bake

Preheat oven to 375°F (190°C). On a lightly floured surface, roll chilled dough into a 12-inch circle. Transfer to a 9-inch (23 cm) tart/quiche pan with removable bottom. Trim/press edges and flute if desired. Chill the lined pan for 10 minutes. Line crust with parchment and fill with pie weights or dried beans. Bake for 15 minutes, remove weights and parchment, then bake 8–10 more minutes until edges set and bottom looks slightly dry. Remove and cool slightly.

Sauté vegetables

While crust chills or bakes, heat 1 tbs olive oil in a skillet over medium heat. Add 0.5 cup diced onion and 0.5 cup diced red bell pepper; cook 4–5 minutes until softened. Add 1 cup sliced mushrooms and sauté 3–4 minutes until they release moisture. Add 2 cups packed spinach and 2 tsp minced garlic; cook until spinach wilts, about 1–2 minutes. Season with 0.5 tsp salt and 0.25 tsp black pepper. Remove from heat and let cool slightly. If vegetables released a lot of liquid, drain in a sieve and press gently to remove excess moisture.

Whisk custard

In a medium bowl, whisk together 4 large eggs until blended. Whisk in 1 cup whole milk and 0.5 cup half-and-half until smooth. Stir in 1 cup grated Gruyère or sharp cheddar, 0.5 tsp salt, 0.25 tsp black pepper, 1 tsp fresh thyme leaves, and 1/8 tsp freshly grated nutmeg.

Assemble quiche

Evenly spread the cooled sautéed vegetables over the pre-baked crust. Pour the egg-and-cheese custard over the vegetables, pressing gently to remove any air pockets. Sprinkle additional 2 tbs grated cheese on top if using.

Bake until set

Reduce oven temperature to 350°F (175°C). Bake the assembled quiche on the middle rack for 30–40 minutes, or until the center is just set (a slight jiggle is okay) and the top is lightly golden. If the crust edge browns too quickly, cover the edge with foil.

Rest

Remove quiche from oven and brush the crust edge with 1 tsp olive oil or melted butter for sheen. Let the quiche rest on a wire rack for 10–15 minutes before slicing to allow the custard to finish setting.