Heat the oil in a non-stick pan over low-medium heat. Add in the chicken sausage and sauté for 6-8 minutes or until you get a nice golden brown on all sides and no longer pink.
Add in the eggs, tomatoes, and cheese. Move the eggs around the pan until they become firm and fluffy but still moist. Remove from the heat. Stir in the scallions and avocado. Season with salt and pepper.