Make the cakes: Preheat oven to 350°F. Line a cupcake tin with paper liners.
Beat the butter and lavender buds in the bowl of an electric mixer for 2 minutes, or until well combined. Scrape down the bowl and beat for 1 more minute. Add the sugar and mix well. Beat in the egg and extracts.
In a separate bowl, whisk together the flour, baking powder, baking soda and salt. Add the flour to the butter mixture alternately with the sour cream on low speed; begin and end with flour. Turn the batter over several times by hand with a large rubber spatula to make sure the lavender buds are well dispersed. Fill each cupcake liner 2/3 full. Bake for 17 minutes, or until a toothpick tester comes out clean. Remove cakes from pan and let them cool completely before frosting.
Make the frosting: In a stand mixer fitted with the whisk attachment, mix together the butter and confectioners’ sugar. Begin on low speed until crumbly; add milk or cream a little at a time until the mixture is spreading consistency. Beat on high 3 minutes. Add lemon extract and beat again for another minute.
Add the lavender gel food color a little at a time until the desired hue is achieved. Transfer frosting to a piping bag fitted with a large French decorator tip and pipe frosting onto the cupcakes. Immediately top with edible gold stars, if using.
Loaf cake: You can double this recipe and bake it in a 9x5 inch loaf pan. Cook time will increase to 40-45 minutes.
Keyword culinary lavender, French butter, lemon extract