Preheat the oven to 350°F and lightly grease a 9x13-inch baking dish.
In a skillet over medium-high heat, cook the pork sausage until browned and crumbled, about 7 minutes. Drain any excess fat.
Combine the eggs, milk, salt, and pepper in a large bowl. Mix well. Stir in the Bisquick mix until just combined. Fold in the cooked sausage and 1 cup of cheddar cheese.
Pour the mixture into the prepared baking dish. Top with the remaining 1 cup of cheddar cheese. Bake in the preheated oven for 30-35 minutes, or until the casserole is set and golden brown on top.