01 - Preheat 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 flour, sugar, baking powder, baking soda, and salt until evenly blended.
03 - In a separate bowl, whisk eggs, oil, yogurt (or sour cream), lemon zest, lemon juice, and vanilla extract until smooth and fully combined.
04 - Pour wet ingredients into dry ingredients. Using a spatula, gently fold together until just moistened. Do not overmix—small lumps are acceptable.
05 - Toss raspberries with 1 tablespoon flour in a small bowl. Gently fold coated berries into the batter, being careful not to crush them.
06 - Divide batter evenly among prepared muffin cups, filling each about 3/4 full.
07 - Bake for 18 to 22 minutes, or until a toothpick inserted into the center comes out clean or with just a few moist crumbs.
08 - Let muffins cool in the pan for 5 minutes, then transfer to a wire rack to cool completely before serving.