1/8 teaspoon ground cloves
11 tablespoons (1 stick plus 3 tablespoons) unsalted butter, room temperature
1/2 cup (packed) golden brown sugar
1/3 cup molasses
1 teaspoon vanilla extract
1/4 teaspoon sea salt
5 ounces extra-bittersweet chocolate (do not exceed 85% cacao), chopped (no pieces bigger than 1/3 inch)
Sift flour, cocoa, baking soda, and spices into medium bowl. Using electric mixer, beat butter in large bowl until smooth but not fluffy. Add the brown sugar, molasses, vanilla, and sea salt; beat until fluffy, about 2 minutes. Add flour mixture; beat just until blended (mixture may be crumbly). Add chopped chocolate; mix just to distribute (if dough doesn't come together, knead lightly in bowl to form ball). Divide dough in half. Place each half on sheet of plastic wrap. Form each into 1 1/2-inch-diameter log. Wrap each in plastic; chill until firm, about 3 hours. DO AHEAD: Can be made 3 days ahead. Keep chilled.