Preheat oven to 400 degrees F
Add all of the ingredients except the salt and pepper to a large bowl and mix thoroughly. I used a hand mixer, but you can also do this with spoon or spatula. Just make sure the egg and cheeses are thoroughly incorporated.
Liberally spray a 12-cup muffin pan with non-stick cooking spray.
Fill each cup with exactly ⅓ of the potatoes. I use a 1" scoop to fill mine, and each cup used 3 scoops.
After you've filled the cups, gently tap the muffin pan on the counter to slightly level out and compact the potatoes.
Bake for 25-30 minutes or the edges are darker and the top is golden brown.
Remove from the oven and allow to sit for 10 minutes.
Run a knife around the edges of each cup and use a fork to help you lift them out.
Serve immediately with additional sour green, if desired.