Adjust an oven rack to the middle position and set the oven to broil.
In an ovenproof 12-inch nonstick skillet set over medium heat, add the bacon and cook until just crisp, 4 to 5 minutes. Then set aside. Add the sausage, cooking until well browned and making sure to break it up as it cooks, about 6 minutes. Set the sausage aside with the bacon and discard all but 1 to 2 tablespoons of the pork fat.
Whisk the eggs and milk together. Add the egg mixture to the skillet with the pork fat, set it over medium heat and stir the eggs using a rubber spatula, scraping and tilting the pan to slide the egg mixture around the pan. Cook until the bottom is set and the top is still wet and glistening, 2 to 3 minutes. Then add in the cooked meats and cheeses, and season with salt and pepper. Use a spatula and press the ingredients into the eggs.
Place in the oven and cook until lightly golden on top and puffed up, 2 to 4 minutes. Then let the frittata rest for 5 minutes before slicing.
Combine the cream cheese, sour cream, Sriracha and scallions in a mixing bowl and season with salt and pepper.
Slide the frittata onto a cutting board and cut into rounds using a 3 1/2-inch-to-4-inch cookie cutter, depending on the size of your bagel. Place a frittata round on each bagel and top with a generous smear of sauce. Serve with a side of Atomic Hash Browns and some extra sauce for dippin'.Atomic Hash Browns:
Heat a 12-inch nonstick skillet over medium heat.
Toss the potatoes with the granulated garlic, paprika, cayenne and some salt and pepper in a medium bowl.
Add half of the butter and half of the oil to the skillet. Let melt, and then add the potatoes, pressing them down with a spatula. Cook until crisp and golden brown on one side, 5 to 7 minutes.
Set a baking sheet or a large plate over the skillet and carefully invert the potatoes onto the baking sheet. Add the remaining butter and oil to the skillet and slide the potatoes back in, un-cooked side down, and cook until golden and crispy on the second side as well, 4 to 5 minutes.
Slide onto a cutting board and cut into wedges to serve.
Recipe courtesy of Jeff Mauro