Spray two 12-cup muffin pans with cooking spray. Set aside.
Place the top rack in the oven to within 6-8 inches of the heating element. Preheat the broiler.
Place the Poblano peppers on a foil-lined baking sheet then place them under the broiler.
Broil for 8-10 minutes on the first side or until blackened in numerous places. Turn them over and place them back under the broiler. Broil another 6-8 minutes until the second side is blackened in numerous places.
Remove from the oven and immediately cover with another baking sheet or a sheet of aluminum foil. Let cool 15-20 minutes.
Remove as much of the skin as possible along with the stem, seeds and membrane. Coarsely chop and set aside.
Adjust oven temperature to 350 degrees.
Place the breakfast sausage in a large nonstick skillet. Cook over medium-high heat until browned.
Add the chopped scallions and cook 2-3 more minutes or until scallions are wilted.
Drain off any excess liquid or grease. Let cool.
Combine the sausage, hash browns, cheese and salt and black pepper in a large bowl.
Whisk together the eggs and milk.
Using a small ladle or measuring cup, fill the prepared muffin pans with equal amounts of the egg and milk mixture.
Then, fill each muffin cup with equal amounts of the sausage/cheese/hash brown mixture.
Bake for 30-35 minutes or until set in the center and just firm to the touch.
Let sit in the muffin pan for 5-10 minutes. Using a paring knife, cut around the muffin to loosen it and gently remove it to serve.