To prep, preheat oven to 375F. Line a muffin pan with 12 paper liners and set aside.
Combine the melted butter, milk, and egg in a medium bowl.
½ cup butter, 1 large egg, 1 cup milk
In a separate bowl, whisk together the flour, baking powder, sugar, and salt. Then add this flour mixture to the bowl of wet ingredients and mix until just combined. Do not overmix, to ensure a tender muffin.
2 cups flour, ⅓ cup sugar, 1 tablespoon baking powder, ½ teaspoon salt
Add the white chocolate chips and raspberries. Fold in gently to evenly distribute without mashing the raspberries.
½ cup white chocolate chips, 1 cup raspberries
Divide the batter among the 12 muffin cups.
Bake in the preheated oven for 24-28 minutes. (26 minutes on convection bake was perfect in my gas oven)
Cool the muffins slightly in the pan, then remove from the pan to finish cooling or to eat while still warm.