Butter and flour 12 regular (1/2-cup) or 6 large (1-cup) muffin tins or line them with paper liners. In a small bowl, sift together both flours, the baking soda, baking powder, salt, cinnamon, and nutmeg. Using a hand mixer or stand mixer fitted with the paddle, cream the butter and sugar in a large bowl until light and fluffy, about 3 minutes. Add the eggs, one at a time, beating well after each addition. Scrape the sides of the bowl and beat in the vanilla. On low speed, add the flour mixture in three additions, alternating with the buttermilk in two additions, beginning and ending with the flour. Gently fold in the berries by hand. Spoon the batter into the muffin cups
to almost full.