Three-Cheese-and-Herb Frittata Sandwiches

1 . Stage

Preheat oven to 475 degrees F. In a 12-inch ovenproof nonstick skillet, melt butter in olive oil. Add onions, thyme, crushed red pepper, bay leaf, and a generous pinch each of salt and pepper. Cover and cook over moderate heat, stirring occasionally, until onions are very soft and browned, about 20 minutes. Discard bay leaf.

2 . Stage

In a large bowl, whisk eggs with crumbled goat cheese, Parmigiano, parsley, chives, 1/2 cup of Gruyère, 1 teaspoon of salt, and 1/4 teaspoon of pepper. Pour egg mixture into skillet and cook over moderately low heat, stirring gently, until eggs start to set, about 5 minutes. Sprinkle frittata with the remaining 1/2 cup of Gruyère. Transfer skillet to oven and bake frittata for 8 to 10 minutes, until center is just set. Run a rubber spatula around the edge of frittata and slide it onto a work surface. Let cool slightly, then cut it into 6 pieces.

3 . Stage

In a medium bowl, toss arugula with vinegar and season with salt and pepper. Brush bagels with butter and fill with frittata, arugula, sliced tomatoes, prosciutto, and basil. Close bagels, cut in half, and serve. Looking for more breakfast recipes? Start the day with one of our French toast recipes, easy quiche recipes, or breakfast casserole recipes that feed the whole family.