Using a stand mixer or handheld mixer, cream butter with sugar for 2 minutes.
Mix in eggs, vanilla, and lemon zest until fully combined.
Alternate adding in dry ingredients with the buttermilk, stirring with a wooden spoon or spatula until just barely combined. If necessary, add an additional tablespoon of buttermilk to help the batter come together. Fold in white chocolate chips.
2 large eggs
Transfer to muffin liners, filling almost to the top of each. Sprinkle each with turbinado sugar. Bake in preheated oven for 8 minutes, then reduce heat to 375°F (without opening oven door).
½ cup unsalted butter
Bake another 15 minutes or until a toothpick entered into a muffin comes out clean. Let cool in muffin pan for 10 minutes, then serve warm or cool on wire racks.
Video
Notes
Buttermilk: I used full fat buttermilk for these muffins, to enhance the richness of the batter. Full fat would be preferable, if you can find it, but low-fat buttermilk works fine as well. If you don’t have buttermilk, you can substitute ⅔ cup of whole milk with 2 teaspoon of the milk replaced with vinegar.Frozen berries: If you use frozen berries, no need to wash or thaw them -- just toss them in the recipe as usual.