Make the cookie dough with a stand mixer: Beat the butter, granulated and brown sugars, and vanilla with a stand mixer, bowl locked, until light and fluffy, scraping down the bowl as needed and mixing until no buttery chunks remain.

Add flour, and mix just until combined and all flour is moistened.

Add chocolate chunks, mix just until incorporated. Mixture will look crumbly.

Make the cookie dough with a handmixer: Use the same process, but you’ll want to start with room temperature or softened butter.

Shape and chill the dough: Transfer dough to a large sheet of parchment paper and form into a log about 2.25 to 2.5 inches in diameter. Chill until totally firm, about 2 hours.

Slice and finish the cookies: When you’re ready to bake the cookies, heat your oven to 350°F. Line one or two large baking sheets with parchment paper.

Lightly beat the egg and brush it over the sides of the chilled cookie logs. Sprinkle the coarse sugar on the open paper or plastic wrap and roll the logs into it, coating them.

Using a sharp serrated knife, cut logs into ½-inch thick rounds. If they break, just squeeze it back together in a disc-like shape.

Bake the cookies: Arrange cookie slices on prepared sheets one inch apart and sprinkle each with a few flakes of salt. Bake for 12 to 15 minutes, or until the edges are just beginning to get golden brown.

Let cool slightly to set before transferring the cookies to wire racks to cool the rest of the way.