Preheat your oven to 350°F and grease a 9 x 11 or equivalent sized casserole dish with butter or cooking spray.
Add 1 tablespoon of olive oil to a large skillet over medium-high heat and add the shallots, red pepper, and a pinch of salt and pepper.
Cook until just soft, about 2-3 minutes, then add the ground sausage.
Cook, breaking up, until no longer pink, about 5-7 minutes.
Meanwhile, heat a second large skillet over medium high, add 1 tablespoon of olive oil, and add the potatoes. Season with just a pinch of salt and pepper.
Cook until the potatoes are just slightly tender, about 10 minutes.
While the sausage and potatoes are cooking, crack your eggs into a medium bowl, season with salt and pepper, and whisk in the milk until blended.
After the sausage and potatoes are done cooking, layer everything into the casserole dish by adding half of the eggs, sausage, potatoes, and cheddar cheese and then repeating with the remaining half.
Bake for about 40 minutes, or until just set in the center.
Topped with fresh herbs like parsley or sliced green onions, if desired.