01 - Preheat oven to 350°F. Grease and flour a 9-inch round cake pan or line with parchment paper.
02 - In a medium bowl, whisk together flour, baking powder, baking soda, salt, and chopped lavender. Set aside.
03 - In a large mixing bowl, combine sugar and lemon zest. Rub together with your fingers to release the aromatic oils.
04 - Add softened butter to the sugar mixture and beat until light and fluffy, approximately 3 minutes.
05 - Beat in eggs one at a time until fully incorporated, then add vanilla extract.
06 - Alternate adding the dry ingredients and milk to the wet mixture, beginning and ending with the dry ingredients. Mix in the lemon juice until just combined; avoid overmixing.
07 - Pour batter into the prepared pan and smooth the top. Bake for 30-35 minutes or until a toothpick inserted in the center comes out clean.
08 - Let the cake cool in the pan for 10 minutes, then turn out onto a wire rack to cool completely before glazing.
09 - Whisk powdered sugar with lemon juice until smooth and pourable. Drizzle over the cooled cake and garnish with additional lavender if desired.