Ingredients
1 1/3 cups unbleached all-purpose flour
1/3 cup buckwheat flour
1/4 teaspoon baking soda
1 teaspoon kosher salt
10 tablespoons unsalted butter, room temperature
2/3 cup packed light-brown sugar
1/2 cup granulated sugar
1 large egg
1/2 teaspoon pure vanilla extract or paste
10 ounces semisweet chocolate chips, such as Guittard (1 1/2 cups)
Flaky sea salt, such as Jacobsen, for sprinkling
Preparation
In a small bowl, whisk together both flours, baking soda, and kosher salt. In the bowl of a mixer fitted with the paddle attachment, beat butter with both sugars on medium-high speed until pale and fluffy, about 4 minutes. Add egg, then vanilla; beat to combine. Reduce speed to low; add flour mixture and beat until just combined. Fold in chocolate. Cover with plastic wrap; refrigerate at least 8 hours and up to 2 days.
Preheat oven to 350 degrees. Remove dough from refrigerator and form into 1 1/2-inch balls (each about 2 heaping tablespoons). Place on parchment-lined baking sheets, 2 inches apart. Sprinkle a few grains of flaky salt on top of each ball. Bake, rotating pans once and banging firmly against a hard surface every few minutes, until cookies are just set and lightly golden around edges, 15 to 17 minutes. Let cool 5 minutes, then transfer to a wire rack and let cool completely.
