01 - Preheat the oven to 375°F. Line a 12-cup muffin tin with paper liners or grease thoroughly.
02 - In a large bowl, whisk together flour, baking powder, baking soda, salt, and black pepper until evenly mixed.
03 - In a separate bowl, beat eggs then whisk in whole milk and olive oil or melted butter until fully combined.
04 - Pour wet ingredients into dry ingredients and gently stir until just combined without overmixing.
05 - Gently fold in grated cheddar, Parmesan, chopped herbs, and any optional add-ins until evenly distributed.
06 - Divide batter evenly among the muffin cups, filling each about three-quarters full.
07 - Bake for 18 to 22 minutes, or until a toothpick inserted in the center comes out clean and tops are golden.
08 - Allow muffins to cool in the tin for 5 minutes, then transfer to a wire rack to cool completely or serve warm.