1. 1. Prepare Your Muffin Tin and Oven: Preheat your oven to 375 F (190 C). Line a 12-cup muffin tin with paper liners or lightly grease each cup to prevent sticking. This ensures easy removal of your baked muffins.

2. 2. Saute the Aromatics and Protein: Heat the olive oil in a large skillet over medium heat. Add the finely chopped onion and bell pepper, cooking until softened, about 5-7 minutes. Stir in your cooked and crumbled sausage or bacon (or vegetarian alternative) and cook for another 2-3 minutes, allowing the flavors to meld. Remove from heat and let cool slightly.

3. 3. Whisk the Wet Ingredients: In a large mixing bowl, whisk together the eggs, milk, salt, and black pepper until well combined and slightly frothy. This aeration helps create a lighter texture in the muffins.

4. 4. Combine Dry Ingredients: In a separate small bowl, whisk together the all-purpose flour and baking powder. This prevents lumps and ensures even distribution of the leavening agent.

5. 5. Assemble the Muffin Batter: Add the cooled sauteed vegetable and protein mixture to the egg mixture. Stir in the shredded cheese and any optional fresh herbs like chives or parsley. Gradually add the flour mixture to the wet ingredients, stirring gently until just combined. Be careful not to overmix, as this can lead to tough muffins. A few small lumps are perfectly fine.

6. 6. Fill the Muffin Cups: Divide the batter evenly among the prepared muffin cups, filling each about two-thirds full. This allows room for the muffins to rise without overflowing.

7. 7. Bake to Golden Perfection: Bake for 20-25 minutes, or until the muffins are set, golden brown on top, and a toothpick inserted into the center comes out clean. The tops should spring back lightly when touched.

8. 8. Cool and Serve: Allow the muffins to cool in the muffin tin for 5 minutes before transferring them to a wire rack to cool completely. This prevents them from becoming soggy and makes them easier to handle. Serve warm or at room temperature.