01 - Preheat oven to 350°F. Grease a 12-cup muffin tin thoroughly or line with cupcake liners for easy removal.
02 - In a medium bowl, whisk together flour, baking powder, baking soda, salt, and chopped lavender until evenly distributed.
03 - In a large bowl, beat softened butter and granulated sugar with an electric mixer until light and fluffy, approximately 2-3 minutes.
04 - Beat in eggs one at a time, ensuring each is fully incorporated before adding the next. Mix in vanilla extract.
05 - Combine whole milk and sour cream in a small bowl, whisking until smooth and uniform.
06 - Add flour mixture to the butter mixture in three additions, alternating with the milk-sour cream mixture. Begin and end with the flour additions. Mix only until just combined to avoid overmixing.
07 - Toss blueberries with 1 tablespoon flour in a small bowl to prevent sinking. Gently fold the coated berries into the batter.
08 - Divide batter evenly among prepared muffin cups, filling each approximately two-thirds full to allow for rising.
09 - Bake for 22-25 minutes or until a toothpick inserted into the center of a cake comes out clean. The tops should be lightly golden.
10 - Allow cakes to cool in the pan for 5 minutes, then carefully transfer to a wire rack to cool completely before glazing.
11 - Whisk powdered sugar and lemon juice in a small bowl until smooth. Drizzle over completely cooled cakes just before serving.