Beat ¾ cup plus 2 tablespoons of room-temperature unsalted butter and 1 cup of sugar with a hand mixer on medium speed until light and fluffy. Beat in 1 cup of tahini.
In another bowl, mix 2 cups of all-purpose flour, 1 teaspoon of baking powder, and 1 pinch of salt. Fold into the butter mixture until a dough forms.
Shape the dough into a log about 2in / 5cm thick, wrap it tightly, and refrigerate for at least 1 hour.
Preheat the oven to 350°F / 175°C and line baking sheets with parchment paper. Slice the log into ½in / 1cm rounds and arrange them 1½in / 4cm apart.
Bake for about 15 minutes, until the edges are light brown and the cookies are set. Cool on the sheets for 10 minutes, then move to a wire rack.
