01 - Preheat the oven to 375°F. Line a standard 12-cup muffin tin with paper liners or lightly grease each cup with butter or cooking spray.
02 - In a large mixing bowl, whisk together all-purpose flour, whole wheat flour, granulated sugar, baking soda, baking powder, and fine sea salt until evenly distributed.
03 - In a separate medium bowl, whisk together buttermilk, egg, and melted unsalted butter until the mixture is smooth and well combined.
04 - Pour the wet ingredients into the dry ingredients. Using a spatula or wooden spoon, stir gently until just combined. The batter should remain slightly lumpy—avoid overmixing to prevent tough muffins.
05 - Gently fold in the raisins and caraway seeds if using, distributing them evenly throughout the batter.
06 - Divide the batter evenly among the prepared muffin cups, filling each about three-quarters full. An ice cream scoop works well for consistent portioning.
07 - Bake at 375°F for 16 to 18 minutes, or until a wooden toothpick inserted into the center of a muffin comes out clean and the tops are golden brown.
08 - Let the muffins cool in the tin for 5 minutes before transferring them to a wire rack. Serve warm with butter and honey, or allow to cool completely before storing in an airtight container.