Step 1

Preheat the oven to 350 degrees Fahrenheit (175°C) and line 2-3 baking sheets with parchment paper.

Step 2

In a large bowl, beat the butter, powdered sugar, and granulated sugar with an electric mixer on medium speed (start on low) until light and fluffy, about 2 minutes.

Step 3

Turn the mixer to low and blend in the egg yolks, lemon juice, and lemon zest until well combined.

Step 4

In a separate bowl, whisk the flour, cornstarch, baking powder, salt, and Kool-Aid (if using) until well blended. Add to the wet ingredients and stir by hand until just combined. If the dough feels very soft, cover and chill for 30 minutes.

Step 5

Portion the cookie dough into 1 tablespoonful-sized balls. Arrange on the baking sheets with 2 inches between them and gently press the tops with the bottom of a glass to flatten slightly.

Step 6

Bake for 10-12 minutes or until the edges are very lightly golden. Leave to cool on the baking sheets for 5 minutes.

Step 7

While the cookies bake, mix the powdered sugar and Kool-Aid in a medium bowl. After the cookies have cooled for 5 minutes, carefully toss them, one by one, in the sugar coating. Place the coated cookies on a wire rack to cool.

Step 8

When the cookies are cool, toss them again in the powdered sugar. Serve and enjoy!