Egg & Sausage Breakfast Sandwiches

From: Culinary Institute of America Breakfasts & Brunches

1/2 C clarified butter or canola oil, divided use
3/4 pound sliced mushrooms
4 C thinly sliced onions
1 Tbsp salt, divided use
2 tsp freshly ground black pepper, divided use
3/4 pound Breakfast Sausage
16 large eggs
1 C grated cheddar cheese
8 toasted bagels, kaiser rolls or English muffins

Heat 2 tablespoons of butter or oil in a saute pan over medium-high heat until almost smoking. Add the mushrooms and saute until lightly caramelized, 5-6 minutes, stirring occasionally. Remove the mushrooms from the pan, reserve.
Heat another 2 tablespoons butter or oil in the same saute pan over medium-high heat. Add the onions and saute until lightly caramelized, 5-7 minutes. Return the mushrooms to the saute pan and season with 1 teaspoon salt and 1/2 teaspoon pepper, or to taste. Reserve warm until needed.
Divide the sausage into 8 equal portions and shape into patties about the size of a bagel. Saute them in batches over medium-high heat until golden brown and cooked thoroughly, 3-5 minutes on each side. Drain on paper toweling and reserve warm until needed.
Whisk eggs in a bowl and season with salt and pepper. Heat 2 tablespoons butter or oil in a large saute pan over medium-high heat until almost smoking. Add the eggs to the pan and stir until they are soft and creamy, 1 1/2 minutes for soft scrambled or 2 minutes for hard scrambled eggs. Remove the eggs from the heat when fully cooked but still moist.
Press the eggs into a thin layer in the saute pan and sprinkle the cheese over the eggs.
For each sandwich, place 1 sausage patty on a toasted bagel. Top with the eggs and the onion-mushroom mixture. Place the top of the bagel on the onion mixture and serve hot.