Pre-heat the oven to 375 with a rack placed in the middle of the oven.Grease muffin tins with soft butter, Pam, oil or use cupcake papers.Whisk all dry ingredients together in a large bowl. Set aside.In a medium bowl, whisk together all wet ingredients, buttermilk, oil, eggs, lemon zest and extract. Stir with a spatula until semi-smooth.Pour wet ingredients into dry ingredients and fold with a spatula until blended, but do not over do it.Prepare frozen berries. In a small bowl, place ½ cup or so of flour, add the frozen berries and toss to coat. Remove the berries from the flour by cupping with your fingers, shaking off the excess flour. Add berries to the batter. Fold lightly with a spatula to distribute the berries into the batter.Spoon batter into muffin tins to fill approximately â…” full.Bake for 20 to 25 minutes, until golden brown or a toothpick, comes out clean when testing in the middle of the muffin.Cool 10 minutes on a rack, then remove the muffins from tin and place on a rack to cool completely.