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 bowl, whisk together 2 cups flour, sugar, baking powder, baking soda, and salt until thoroughly combined.
03 - In a separate medium bowl, whisk eggs, oil, yogurt or sour cream, lemon zest, lemon juice, and vanilla extract until smooth and well blended.
04 - Pour wet ingredients into dry ingredients. Using a spatula, fold together gently just until flour disappears. Do not overmix—small lumps are acceptable.
05 - Toss raspberries with 1 tbsp flour in a small bowl, then gently fold into batter until evenly distributed.
06 - Divide batter evenly among 12 muffin cups, filling each approximately 3/4 full.
07 - Bake for 18 to 22 minutes until a toothpick inserted into the center comes out clean or with a few moist crumbs.
08 - Let muffins cool in pan for 5 minutes, then transfer to a wire rack to cool completely before serving.