Step 1

Butter a 9"-x-13" casserole dish. Heat oil in a large nonstick skillet over medium heat and cook the mushrooms, stirring occasionally, until lightly golden brown, 6

Step 2

to 8 minutes. While the mushrooms are

Step 3

cooking, partially split the croissants, making sure not to cut all the way

Step 4

through. Stuff with spinach and all but 1/2 cup cheese and transfer to the

Step 5

prepared dish, cut sides facing up. Divide mushrooms among the stuffed

Step 6

croissants. In a bowl, beat eggs

Step 7

with milk and 1/2 teaspoon each salt and pepper, then pour over the croissants.

Step 8

Sprinkle remaining 1/2 cup cheese over the top. Cover with foil, then plastic

Step 9

wrap; refrigerate overnight (or at least 15 minutes). When ready to serve, heat

Step 10

oven to 375 degrees F, remove casserole from fridge and discard plastic wrap. Bake for 20 minutes, then remove foil and bake until eggs are puffed and just set, 25 to

Step 11

30 minutes more.