Preheat your oven to 375°F and generously coat the wells of a muffin tin with nonstick cooking spray to prevent sticking.

Pat dry the filling ingredients, such as the diced ham and chopped bell peppers, using paper towels to eliminate excess moisture that could affect the consistency of the muffins.

In a large mixing bowl, crack the eggs and gently pierce the yolks. Add the half-and-half, salt, pepper, and garlic powder. Whisk the mixture until the ingredients are just combined, taking care not to overmix.

Combine the prepared filling ingredients in a separate bowl. Distribute about 2 tablespoons of the filling mixture into each muffin tin. Carefully pour or ladle the egg mixture over the fillings, ensuring each tin is nearly full while leaving a small gap at the top.

Place the muffin tin in the preheated oven and bake for 18 to 20 minutes. The centers of the muffins should remain slightly jiggly, as they will firm up further while cooling outside the oven.

Once baked, allow the muffins to cool in the tin for about 5 minutes. Expect a slight deflation, which is normal. Use a butter knife to loosen the edges, then gently lift the muffins from the tin. Serve immediately while warm.