01 - Preheat the 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 citrus oils.
04 - Add softened butter to the sugar mixture and beat until light and fluffy, about 3 minutes.
05 - Beat in eggs one at a time, 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; do not overmix.
07 - Pour batter into the prepared pan and smooth the top.
08 - Bake for 30-35 minutes or until a toothpick inserted in the center comes out clean.
09 - Cool the cake in the pan for 10 minutes, then turn out onto a wire rack to cool completely.
10 - For the glaze, whisk powdered sugar with lemon juice until smooth and pourable. Drizzle over the cooled cake. Garnish with additional lavender if desired.