In a stand mixer fitted with whisk attachment or by hand, beat the butter and sugars together until smooth. Add the egg, milk, and vanilla until mixed thoroughly.

In a separate bowl, sift together the flour, baking powder, and salt. Add the dry mixture to the wet mixture and mix until incorporated. Fold in the chocolate chips.

Chill the dough for at least one hour or up to 24 hours.

Preheat the oven to 400 degrees Fahrenheit.

Dust your work surface with flour to keep the dough from sticking. I like to cut the dough in half and roll out in batches. Roll out the dough to 1/4-​ to 1/2-​inch thick. Using a round cookie cutter, cut out and place the dough onto a baking sheet lined with Gefen Parchment Paper or silicone baking mat. To keep the dough from sticking to your cutter, dip cookie cutter in flour.

Fill each round with half a teaspoon of your choice of chocolate hazelnut spread, dulce de leche, cookie butter or a few chocolate chips and mini marshmallows. Pinch up the dough to form a triangle. Pinch dough very tightly to ensure they do not open. Place cookies on a baking sheet lined with parchment or a silicone baking mat.

Repeat with remaining dough, putting scraps back into dough three or four times until all the dough has been used. If dough becomes too soft, pop into the freezer for five minutes to chill slightly.

Place cookies in freezer for five minutes or refrigerate for 10 to 15 minutes.. This step will ensure the cookies don’t spread too much or open during the process of baking.

Bake for eight minutes, or until cookies are just golden around the edges. Allow to cool completely on a wire rack.