Heat oil in 10-inch, nonstick skillet over medium heat. Add mushrooms and peppers and cook until tender, about 10 minutes. Remove from heat and stir in green onions and chicken sausage.
Divide sausage mixture equally between 4 oven safe ramekins. Crack 1 egg into center of each cup. Transfer cups to rimmed baking sheet. Bake until egg whites are almost set, about 15 minutes. Season with salt and pepper before serving.
