Make the cookies: Preheat the oven to 350°. In a medium bowl, combine the butter, tahini, sugar and salt. Using an electric hand mixer, beat the mixture until light and fluffy, 2 minutes. Add the flour and mix until a dough comes together. Wrap in plastic wrap and refrigerate for 30 minutes.
Meanwhile, make the ganache: In a medium bowl, combine the chocolate chips, tahini, honey and kosher salt. In a small saucepan, bring the heavy cream to a simmer, then pour the cream over the chocolate mixture. Let sit for 2 minutes, then whisk until smooth. Let cool completely then transfer to a piping bag fitted with a large star tip.
Line 2 baking sheets with parchment paper and set aside. On a lightly floured surface, roll the dough out into a 14-inch circle, ⅓ inch thick. With a 2¼-inch round cutter, cut out 40 circles, rerolling scraps as needed. Transfer to the prepared baking sheets, 1 inch apart, and sprinkle with the sesame seeds. Bake until lightly golden, 18 to 20 minutes.
Pipe 3 tablespoons cooled ganache onto half of the cookies, then top with the remaining cookies to sandwich together and serve.