Preheat the oven to 300 degrees. Grease a large rimmed baking sheet.
In a large bowl, beat together the eggs, then add the bell peppers and chicken sausage. Season with salt and black pepper. Pour the mixture into the prepared pan, making sure the vegetables and sausage are distributed evenly.
Bake for about 25-30 minutes, until the eggs are just set. Remove from the oven and let rest for 5 minutes. Slice into 10 to 12 pieces. Save what you don’t plan to use immediately in the freezer or refrigerator.
Before the eggs are done, toast as many English muffins as you plan to make, and prepare your avocado mash.
Take an English muffin and on one side, spread out the avocado mash. Top with an egg square. On the other muffin side, spread out your cream cheese (if using) and place on top of the egg square. Repeat until all sandwiches are made. Serve.