Preheat oven to 375˚F.
Generously grease a 12-cup muffin pan with cooking spray.
Cook diced bacon until crisp in a large 12-inch skillet set over medium-high heat.
Remove cooked bacon with a slotted spoon and set aside. DO NOT discard the bacon grease.
Set skillet back over medium-high heat and add potatoes and vegetables. Season well with salt and pepper and cook for 6 to 8 minutes, or until potatoes are tender.
Remove from heat and stir in 2/3 of the prepared bacon.
Evenly divide and spoon veggie mixture into the muffin pan; top each with cheddar cheese. Set aside.
In a mixing bowl combine eggs, milk, and parmesan cheese; whisk until thoroughly incorporated.
Pour milk mixture over each muffin cup. Add remaining bacon pieces over each muffin.
Bake for 13 to 15 minutes, or until eggs are set.
Remove from oven and let cool 5 minutes in the pan.
Remove from pan and serve.