Ingredients

1 cup cake flour
1/2 teaspoon baking soda
1/2 teaspoon fine salt
6 tablespoons unsalted butter
6 tablespoons packed light brown sugar
1/3 cup granulated sugar
1 large egg
1/2 teaspoon pure vanilla extract
1 cup semisweet chocolate chips
1 tablespoon multicolored sprinkles

Directions

Position a rack in the center of the oven, and preheat to 375 degrees F. Line 1 large rimmed baking sheet with parchment. Whisk together the flour, baking soda and salt in a small bowl.

Microwave the butter in a large microwave-safe bowl on high until completely melted, about 1 minute. Whisk in both sugars, then the egg and vanilla, until incorporated and smooth; let cool for 5 minutes. Stir in the flour mixture with a wooden spoon until just incorporated. Stir in the chocolate chips.

Scoop the dough onto the center of the prepared baking sheet. Spread the dough with an offset spatula into an 8-inch circle that’s 1/2 inch thick. Sprinkle the top of the cookie with the sprinkles (they’ll look crowded but will spread out as the cookie bakes).

Bake, rotating the baking sheet from back to front halfway through, until golden but still soft in the center, 22 to 25 minutes. Let cool for a few minutes on the baking sheet, then use a large spatula to transfer the cookie to a rack to cool. Slice the cookie into wedges, and serve.