Prep the pan: Preheat your oven to 375°F (190°C). Lightly grease a standard 12-cup muffin tin with cooking spray or a thin layer of oil. This helps prevent sticking and makes cleanup easier.

Form the ham “cups”: Press one slice of ham into each muffin well. Let the edges ruffle up the sides to create a cup shape. If your ham is very thin, double up a few cups to avoid tearing.

Whisk the eggs: In a large bowl, whisk eggs, milk, salt, pepper, garlic powder, and onion powder until smooth and slightly frothy. This adds air and keeps the texture soft.

Add mix-ins: Stir in the shredded cheese, green onions, and bell pepper if using. Save a little cheese to sprinkle on top for a golden finish.

Fill the cups: Divide the egg mixture evenly among the ham-lined muffin wells, filling each about three-quarters full. Do not overfill or they will spill as they puff up.

Top and bake: Sprinkle the remaining cheese over the cups. Bake for 14–18 minutes, until the eggs are set in the center and the edges of the ham look lightly crisp.

Rest and release: Let the cups rest in the pan for 3–5 minutes. Run a small spatula or butter knife around the edges to loosen and lift them out gently.

Finish and serve: Taste and add a pinch of salt or pepper if needed. Serve warm as is, or with hot sauce, salsa, or a dollop of Greek yogurt.