An ‘impossible” quiche is one that’s made with a flour-thickened custard in lieu of a traditional pie crust. During baking, the flour helps form a “crust” on the bottom of the quiche. This quiche was very easy to make and I will definitely make it again.
3 TBS finely grated Parmesan Cheese
8 oz Gruyere cheese, shredded (2 cups) ** (see note below)
4 oz thickly sliced deli ham, chopped
4 green onions, minced
1/2 cup flour
3/4 tsp baking powder
1/2 tsp pepper
1/4 tsp salt
1 cup half-and-half
2 TBS melted unsalted butter
4 large eggs, lightly beaten
1/8 tsp ground nutmeg
Adjust oven rack to lowest position and heat oven to 350 degrees. Grease a 9-inch pie plate with softened butter and coat evenly with Parmesan cheese.
Combine cheese, ham, and onions in a bowl. Spread ham and cheese mixture evenly in bottom of greased pie pan. Combine flour, baking powder, pepper and salt in the now-empty bowl. Whisk in half-and-half, eggs, melted butter, mustard and nutmeg until smooth. Slowly pour batter over ham and cheese mixture in the pan.
Bake until quiche is light golden brown and filling is set, 30-35 minutes. Cool on wire rack for 15 minutes. Slice into wedges. Serve warm.
I baked this the night before and refrigerated it. I warmed individual slices in the microwave the following day and served with hash browns and sausage. It tasted great!
** I used 1 cup Swiss & 1 cup Monterey Jack instead of the Gruyere cheese as Gruyere can be very expensive.
Source: - America's Test Kitchen - Cook's Country