Preheat oven to 350 degrees. Place oven racks in upper and lower thirds of oven.
In a medium bowl, whisk together the flour, baking powder, and salt.
Using an electric mixer on medium speed, beat butter, sugar, and honey together until light and fluffy, about 3 minutes. Mix in tahini, then add dry ingredients in three batches, beating after each addition until fully combined. Dough will be slightly sticky.
Place sesame seeds in small bowl. Scoop out tablespoons of dough (about 1 ounce) and roll into balls. Dip one side of balls in sesame seeds, gently pressing to adhere, and place, sesame side up, on two parchment-lined baking sheets roughly 2 inches apart.
Bake cookies, rotating sheets halfway through, until they are golden brown, about 13-15 minutes. Allow to cool on baking sheets (cookies will firm as they cool).