In a small bowl, combine All-Purpose Flour (1 1/4 cup), Baking Powder (1/2 teaspoon), and Kosher Salt (1/4 teaspoon) together. Set aside.
Beat the Butter (8 tablespoon) and Granulated Sugar (1/2 cup) in a stand mixer, using the paddle attachment, on medium-high until fully whipped. Slowly add the Tahini (1/2 cup) and Honey (1/2 tablespoon), continuing to whip at a medium-high speed.
Reduce the mixer speed to low and gradually add the flour mixture until a dough has just formed.
Transfer dough to a cutting board and roll into a long tube. Place in the center of a sheet of plastic wrap, then wrap and chill in the refrigerator for at least 1 hour, until dough is firm.
Preheat oven to 350 degrees F (180 degrees C) and line 2 baking sheets with parchment paper.
Remove the chilled dough from the refrigerator and side the dough until 1/4-inch slices. Place the cookies about an inch a part on the cookie sheet. Top each cookie with a few Pistachios (1/2 cup).
Bake for approximately 15 minutes.
Allow cookies to cool on the baking sheets and completely before serving. The longer the cool, the less likely they are to crumble!