Preheat oven to 350°F (175°C).
Grease a 12-cup muffin pan or use silicone liners.
In a saucepan, melt 1½ Tbsp. ghee. Whisk in hot sauce, coconut aminos, and cayenne pepper to make buffalo sauce. Set aside.
In a skillet, melt remaining ghee over medium heat. Sauté bell pepper and green onions for 5 minutes.
Turn off heat and stir in spinach, chicken, and buffalo sauce.
Divide mixture evenly into muffin cups.
Beat eggs with salt and pepper, then pour over filling.
Bake Buffalo Chicken Egg Muffins for 18–20 minutes until set.
Cool slightly, remove, and serve.