Pre-heat the oven to 350 degrees F. Line two baking sheets with parchment paper or silicone pads (Silpat). Add the butter and sugar to a large bowl. Using a hand mixer, cream the butter and sugar together until smooth. Add the tahini, maple syrup and vanilla and blend until combined. Add the flour, baking powder and salt and mix the dough together by hand, using a rubber spatula. If the dough is too wet add another tablespoon of flour, stirring to combine. Refrigerate the dough for at least 30 minutes.