01 -
Set oven temperature to 350°F and line a baking sheet with parchment paper or a silicone mat.
02 -
In a bowl, melt butter, then mix in granulated sugar, egg yolks, vanilla extract, and green gel food coloring until uniformly blended.
03 -
Add all-purpose flour, baking soda, and salt to the wet mixture; stir gently until the dough just comes together.
04 -
Flatten the dough in the bowl, divide into two halves, then form six equal dough balls from each half.
05 -
Roll each dough ball in extra granulated sugar, then arrange them spaced evenly on the prepared baking sheet.
06 -
Bake cookies for 10 to 11 minutes, or until they are puffed and display surface cracks.
07 -
While cookies are still hot, press one red heart sprinkle firmly into the center of each cookie.
08 -
Allow cookies to rest on the baking sheet for 2 minutes before transferring them to a wire rack to cool completely.