Preheat oven and spray:
Set oven to 350°F (175°C). Spray muffin tin cups with nonstick cooking spray.Distribute veggies and bacon:
Evenly distribute diced bell peppers, bacon crumbles, and chopped spinach among the prepared muffin cups.Beat eggs with seasonings:
Beat the eggs thoroughly. Using a quart-size glass measuring cup makes pouring easier. Mix in chives, salt, and black pepper.Pour egg mixture:
Pour the egg mixture evenly into each muffin cup.Bake until set:
Bake for 18-22 minutes until the eggs are fully set.Serve warm:
Serve while warm.