How to Make It
Preheat the oven to 350°. Line 2 large baking sheets with parchment paper. In a medium bowl, whisk the flour with the baking powder, salt and nutmeg. In a stand mixer fitted with the paddle, beat the butter with 1 1/2 cups of the sugar at medium speed until light and fluffy, about 3 minutes. Beat in the egg and vanilla until incorporated, about 1 minute. At low speed, mix in the dry ingredients until just combined.
Spread the remaining 1/2 cup of sugar in a shallow bowl. Scoop 2-tablespoon-size mounds of dough, roll them in the sugar and place them on the prepared baking sheets, about 2 inches apart. Bake the cookies for 12 to 14 minutes, until the edges are just set and lightly golden brown; rotate the sheets from top to bottom and front to back halfway through baking. Let the cookies cool on the sheets for a few minutes, then transfer them to a wire rack to cool completely.