Ingredients

• Nonstick cooking spray
• 6 ounces thinly-sliced deli ham, torn into quarters
• 4 whole-wheat English muffins, split, toasted and halved
• 1/2 cup sundried tomatoes not in oil (about 14), sliced
• 4 scallions, trimmed and cut into 2-inch pieces
• 2/3 cup shredded extra-sharp Cheddar, divided
• 4 large eggs
• 3 large egg whites
• 3 cups reduced-fat milk (2 percent)
• 1 tablespoon Dijon mustard
• Kosher salt and freshly ground black pepper

Instructions

1. Lightly mist a round 2-quart casserole dish with cooking spray. Alternately place the ham and muffins in the dish to make a shingled pattern. Sprinkle the sundried tomatoes, scallions and 1/3 cup cheddar over the casserole.
2. In a large bowl, whisk the eggs, egg whites, milk, and mustard; season with salt and pepper. Pour the custard filling over the casserole and sprinkle with the remaining 1/3 cup cheese. Cover the casserole with plastic wrap; refrigerate at least 5 hours and up to overnight.
3. Preheat the oven to 350 degrees F. Place the casserole on a large rimmed baking sheet; bake until golden around edges and just set, about 1 hour. Let stand 10 minutes before serving.