Pour the mixture into your lined baking dish. Sprinkle the remaining cheese on top. Bake for 27-30 minutes, until center is set. Allow to slightly cool before slicing- leftovers can be stored in the refrigerator for up to 5 days.
Heat a large pan over medium heat with the oil. Once hot, add the chicken sausage and the broccoli. Season with 1/2 tsp sea salt, 1/4 tsp black pepper, plus the onion powder and garlic powder. Cook, stirring occasionally, until broccoli is tender and chicken sausage is slightly crisped, about 5-7 minutes. Remove from heat and set aside to cool.
Preheat oven to 350°F and line an 8×8″ baking dish with parchment paper.
In a large bowl, whisk the eggs. Stir in 1/2 tsp sea salt, 1/4 tsp pepper, the oat flour, the baking powder, and 1/2 cup of the cheese. Fold in the broccoli and chicken sausage mixture.