In a large bowl, mix together the flour, baking powder, salt, and sugar.
Add the vegetable oil and milk to the dry ingredients, stirring until just combined.
Lightly grease a cast-iron skillet or a pizza stone. Press the dough into the bottom of the skillet or stone to form a crust.
Preheat your campfire or grill to medium heat.
Sprinkle half of the mozzarella cheese over the crust.
In a separate bowl, beat the eggs and season with salt and pepper. Pour the eggs evenly over the cheese.
Top the eggs with the cooked sausage, diced bell peppers, green onions, and the remaining mozzarella cheese.
Cover the skillet with aluminum foil or a lid to help the eggs cook evenly.
Place the skillet over the campfire or on the grill, cooking for about 15-20 minutes or until the eggs are set and the cheese is melted.
Remove from heat and let cool for a few minutes before slicing and serving.