Step 1

Adjust an oven rack to the middle of the oven. Preheat the oven to 350°F. Line three sheet pans with parchment paper. (If you don’t have 3 baking sheets, you can reuse the parchment and baking sheets, just let the sheets cool off between each round.)

Step 2

In a medium bowl, combine the flour, baking soda, and salt.

Step 3

In the bowl of a stand mixer fitted with a paddle, beat the butter on medium speed until creamy, about 1 minute. Add the brown sugar and the molasses and beat on medium speed until light and fluffy, 2 to 3 minutes. Add the egg, yolk, and vanilla, and beat on medium speed until combined. Add the flour mixture and beat on low speed until just combined.

Step 4

Place the granulated sugar in a medium bowl.

Step 5

Form the cookies into 1 1/2-ounce balls (2 tablespoons). Roll each ball in the sugar and place 8 cookies on each sheet pan.

Step 6

Bake one pan at a time, rotating halfway through baking. Bake until the sides are set and the bottoms are light golden brown, 10 to 11 minutes.

Step 7

Transfer the sheet pan to a wire rack and let the cookies cool for 5 to 10 minutes on the pan, then remove them and let them cool completely on the wire rack.