Ingredients
- teaspoon sbutter, or as needed
- 3/4 cup sslice d crimini mushrooms
- English muffins, split and toasted
- cup sshredded Colby-Monterey Jack cheese, divided
- pound fresh asparagus, trimmed and cut into 1-inch piece s
- 1/2 cup chopped red bell pepper
- 1/2 onion, finely chopped
- cup smilk
- eggs
- teaspoon salt
- teaspoon dry mustard powder
- 1/4 teaspoon ground black pepper
Instructions
- Melt butter in a skillet over medium heat. Add mushrooms; cook and stir until beginning to brown and most of their liquid has evaporated, about 10 minutes.
- Grease a 9x13 inch baking dish. Arrange eight muffin halves, cut side up, in the bottom of the dish. Tear remaining muffins into smaller pieces and use to fill any open spaces. Sprinkle with 1/2 of the cheese, then top with asparagus pieces, mushrooms, red pepper, and onion.
- Whisk milk, eggs, salt, mustard powder, and black pepper together in a bowl; pour over muffins and vegetables. Cover the dish and refrigerate, 8 hours to overnight.
- The next day, remove the casserole from the refrigerator and let stand for 30 minutes. Spread remaining cheese over the top.
- Meanwhile, preheat the oven to 375 degrees F (190 degrees C).
- Bake the casserole in the preheated oven until a knife inserted near the edge comes out clean, 40 to 45 minutes. Let stand for 5 to 10 minutes before cutting into squares.