In a food processor, pulse the flour, almond meal, sugar and salt until combined. Add the butter and pulse until the mixture forms large clumps.
Turn the dough out onto a work surface and knead gently until it comes together. Divide the dough in half and press each half into a disk. Roll out each disk between 2 sheets of waxed paper to 1/4 inch thick. Cut cookies with a 1/2 inch cookie cutter, leaving in the disk. Slide the wax paper-covered disks onto a baking sheet and freeze for at least 1 hour, until firm.
Preheat the oven to 350 degrees and line 2 large baking sheets with parchment paper. Peel off the wax paper, press out cookies and place on baking sheets, about 1 inch apart. Reserve leftover dough to re-roll and make more cookies. Lightly brush the cookies with the egg and sprinkle with the sesame seeds.
Bake the cookies for 17-20 minutes until they are lightly browned; shift the baking sheets from top to bottom and front to back halfway through. Let the cookies cool on the baking sheets for 3 minutes then transfer them to a wire rack and let them cool completely.