Frosted lemon cookies are the perfect warm weather treat for sharing. Soft and tender sugar cookies are topped with sweet buttercream frosting and bursting with fresh lemon flavor.
In a large bowl, add room temperature butter and sugar. Using a hand mixer or stand mixer, beat until light and fluffy, about a minute. Add eggs, lemon zest, and vanilla extract and beat until fully incorporated and fluffy, about a minute.
In a separate bowl, sift together the flour, baking powder, and salt. Gradually stir (or use a mixer on low speed) dry ingredients into butter mixture until just combined.
Cover bowl and chill dough in the refrigerator for 30 minutes. Refrigerating allows time for flavors to meld and also creates a firmer dough that's easy to roll into balls.
Preheat oven to 350℉ and line a baking sheet with parchment paper. Set aside.
Remove dough from refrigerator. Scoop dough using a medium 1.5 inch cookie scoop or shape by hand into 1.5 inch balls.
Place cookie dough balls 2 inches apart onto prepared baking sheet. Gently flatten balls slightly using your hands or the bottom of a glass dusted with flour (to prevent sticking).
Bake for about 10-12 minutes, or until tops look set and edges barely begin to lightly brown (times will vary based on your own oven and size of cookies). Allow to cool for 5 minutes before removing to a wire rack to cool completely.
Frosting
In a medium bowl, add room temperature butter, confectioner's sugar, lemon juice, lemon zest, and salt. Use a hand mixer to whip until frosting is smooth and spreadable. Add milk as needed to achieve desired consistency.
Use an offset spatula or knife to spread frosting over cooled cookies. Optionally, add lemon zest as a garnish.
Allow to air dry for a few hours before storing (frosting will crust on the outside but the inside remains soft, so pressure can cause the frosting to indent).
Notes
* How to measure flour properly: Use a kitchen scale to measure flour for accurate results every time. If you don't have a kitchen scale, use the spoon and level method. Stir the flour (especially if it's been packed down in a bag/container), then gently spoon into the measuring cup, leveling off the top with a knife. Scooping with a measuring cup compacts flour into the cup and adds up to 25% extra to the recipe, resulting in dry, bland cookies that don't spread properly.
Dough storage: Cookie dough will keep in refrigerator for 2-3 days, or up to 3 months in the freezer.
Cookie storage: Cookies will keep for up to 5 days in a tightly sealed container at room temperature. Add a slice of bread to the cookie container to help keep cookies moist. Replace as needed (bread will dry out).