Preheat your oven to 350 degrees Fahrenheit.

Line a baking sheet with parchment and set aside.

In a large mixing bowl, beat together the butter and sugars, 1-2 minutes. Mixture will be crumbly.

Add egg and egg yolk, peppermint extract, and a generous amount of green gel food coloring.

In a separate bowl, whisk together flour, salt, and baking powder.

Add half of the dry ingredients, and mix. Add the remaining, and mix until combined. Dough will be crumbly.

Use a 1 1/2 inch cookie scoop to scoop out the dough, and use your hands to press the mixture into a ball.

Place onto the parchment.

Bake 7-9 minutes.

Remove from the oven and allow to cool 1-2 minutes.

Press a Hershey kiss into each cookie, and allow the cookies to cool 5 minutes more.

Transfer the cookies to a cooling rack, and chill in the refrigerator 20-30 minutes to allow Hershey kisses to set.