In a bowl, use a hand mixer on medium speed to beat together the butter and sugar until pale and fluffy, about 2—3 minutes.

Add the egg and beat until smooth.

Add the flour and mix on low speed until just combined.

Transfer the dough to a work surface and form it into a ball.

Halve the ball and form each half into a flat disk.

Wrap the disks separately in plastic wrap and refrigerate until chilled, about 1 hour.

Preheat the oven to 350ºF (175ºC).

Transfer one disk to a lightly floured work surface and use a rolling pin to roll it out to ¼″ thickness.

Using a 1½″ round or fluted cookie cutter, cut out rounds and transfer them to parchment paper-lined baking sheets, spacing them 1″ apart.

Repeat with the remaining dough disk.

Bake the cookies, rotating the baking sheets top to bottom and front to back halfway through cooking, until the cookies are set but not browned, about 8—10 minutes.

Let cool before serving.