01 - Preheat oven to 350°F (175°C). Grease and flour an 8-inch round cake pan, ensuring even coverage on all surfaces.
02 - In a medium bowl, whisk together all-purpose flour, baking powder, and salt until uniformly blended. Set aside.
03 - In a large mixing bowl, beat softened butter and granulated sugar using an electric mixer until the mixture becomes pale, light, and fluffy, approximately 3-4 minutes.
04 - Incorporate eggs one at a time, beating thoroughly after each addition. Mix in finely chopped culinary lavender buds and vanilla extract until evenly distributed.
05 - Alternately add the flour mixture and whole milk to the butter mixture, beginning and ending with flour. Mix on low speed until just combined, avoiding overmixing.
06 - Pour batter into the prepared cake pan. Using a spatula, smooth the top surface evenly to ensure uniform baking.
07 - Bake on the center rack for 25-30 minutes until a toothpick inserted into the center emerges clean and the top springs back when lightly touched.
08 - While cake bakes, combine water, sugar, and lavender buds in a small saucepan. Simmer gently for 3 minutes. Strain through a fine-mesh sieve and set aside to cool slightly.
09 - Allow cake to cool in pan for 10 minutes. If using syrup, poke small holes across the surface with a toothpick and lightly brush with warm lavender syrup. Cool completely on a wire rack.
10 - Whisk together powdered sugar, fresh lemon juice, and finely chopped lavender buds until smooth. Drizzle glaze over the completely cooled cake. Allow glaze to set for 10-15 minutes before slicing and serving.