- PREHEAT ooven to 350F. Position racks in top and bottom thirds of oven. Line 2 baking sheets with parchment.
- STIR flour with cocoa powder and salt in a medium bowl.
- BEAT butter with sugar in a large bowl, using a wooden spoon, until smooth, 1 min. Gradually stir in half of flour mixture, until just combined. Add remaining flour mixture, kneading with your hands, until dough forms a ball.
- ROLL out on a floured counter until 1/4 in. thick. Cut out cookies with various shapes of cookie cutters. Arrange on prepared sheets, 2 in. apart. Cookies will spread as they bake. Sprinkle cookies with sea salt.
- BAKE in top and bottom thirds of oven, switching sheets halfway through, until edges are just golden, 12 to 15 min. Leave on sheet for 5 min, then transfer cookies to a rack to cool completely. Cookies will keep well in an airtight container up to 1 week, or freeze up to 1 month.
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