If you are using the Ninja Foodi, use the saute function to brown the sausage in the pot of the foodi. If you are using an air fryer, you can use a skillet to do this.
Add in the onion and pepper and cook along with the ground sausage until the veggies are soft and the sausage is cooked.
Using the 8.75 inch pan or the Air Fryer pan, spray it with non-stick cooking spray.
Place the ground sausage mixture on the bottom of the pan.
Top evenly with cheese.
Pour the beaten eggs evenly over the cheese and sausage.
Add fennel seed and garlic salt evenly over the eggs.
Place the rack in the low position in the Ninja Foodi, and then place the pan on top.
Set to Air Crisp for 15 minutes at 390 degrees.
If you are using an air fryer, place the dish directly into the basket of the air fryer and cook for 15 minutes at 390 degrees.
Carefully remove and serve.