Four-Flavor Shortbread Cookies

In a bowl, combine room temperature butter or margarine, eggs, powdered sugar, vanilla extract, and baking powder. Mix well.

Gradually work in the flour and knead until you have a soft, tender dough—it shouldn't be sticky and should feel about the texture of an earlobe.

Divide the dough into 4 equal portions.

Mix pistachios into one portion, cocoa into the second, almonds into the third, and chocolate chips into the fourth. Feel free to swap in other mix-ins if you prefer.

Shape the dough by pressing the different flavored portions together.

Wrap the log in plastic wrap or a bag and freeze for about 15 minutes until the dough firms up a bit.

Once it's firmer, slice it into pieces with a sharp knife.

Transfer to a baking sheet lined with parchment paper and bake in a preheated 350°F (175°C) oven for about 15–17 minutes.