01 - Preheat the oven to 375°F. Line a 12-cup muffin tin with paper liners or grease lightly with cooking spray.
02 - In a large mixing bowl, whisk together the flour, sugar, baking powder, baking soda, and salt until well blended.
03 - In a separate bowl, whisk the eggs, oil, yogurt or sour cream, lemon zest, lemon juice, and vanilla extract until smooth and fully incorporated.
04 - Pour the wet ingredients into the dry ingredients. Fold gently with a spatula until just combined; do not overmix as this will result in tough muffins.
05 - Toss the raspberries with 1 tablespoon flour to prevent sinking, then gently fold them into the batter until evenly distributed.
06 - Divide the batter evenly among the prepared muffin cups, filling each about three-quarters full.
07 - Bake for 18 to 22 minutes, or until a toothpick inserted into the center of a muffin comes out clean or with a few moist crumbs.
08 - Allow the muffins to cool in the pan for 5 minutes before transferring to a wire rack to cool completely.