Preheat your oven to 375°F (190°C) and line a 12-cup muffin tin with paper liners or grease thoroughly with cooking spray. Position your oven rack in the center position for even baking.
In a large bowl, whisk together flour, baking powder, baking soda, and salt. Create a small well in the center of your dry ingredients.
In a separate medium bowl, whisk eggs until frothy (approximately 30 seconds of whisking), then add buttermilk, honey or maple syrup, melted butter, and vanilla extract.
Pour the wet ingredients into the well of dry ingredients and stir gently just until combined. The batter should look somewhat lumpy—this is perfect! Avoid overmixing.
Fold in your choice of savory mix-ins until just distributed. Pro tip: toss cheese or vegetables with 1 teaspoon of flour before adding to prevent sinking.
Fill muffin cups about ⅔ full (approximately 3 tablespoons of batter per cup).
Bake for 18-20 minutes, or until tops are golden brown and a toothpick inserted in the center comes out clean.
Allow muffins to cool in the pan for 5 minutes before transferring to a wire rack. This crucial resting period allows the structure to set.