STEP 1

Whisk together flour, baking soda, baking powder, spices, salt, and pepper. Beat butter with brown sugar on medium-high speed until light and creamy, 2 to 3 minutes. Add eggs, one at a time, beating to combine after each addition, and scraping down bowl as needed. Beat in molasses. Add flour mixture; beat on low until just combined. Divide dough into thirds; form each into a flat rectangle and wrap in plastic. Refrigerate until cold, at least 1 hour and up to 2 days; or freeze up to 2 months (thaw in refrigerator before using, at least 8 hours).

STEP 2

Preheat oven to 350°. Line baking sheets with parchment. Roll out dough a generous 1/8 inch thick, one disk at a time, between lightly floured sheets of parchment, flipping the entire thing and occasionally lifting off parchment and then returning to avoid sticking. Transfer to a baking sheet; refrigerate 30 minutes. Stamp out shapes using the nested snowflake cutters (we used the two largest ones). Transfer cutouts to prepared sheets, spaced about 1 inch apart. Reroll scraps once; stamp out more shapes and transfer to sheets. Refrigerate until firm, about 30 minutes, or freeze 10 minutes. Bake, tapping sheets on counter or oven rack halfway through to flatten tops, until set but not dark, 12 to 14 minutes. Transfer sheets to wire racks; let cool completely.

STEP 3

Fill a pastry bag fitted with the smallest tip (Ateco 800) from the plain round tip set with royal icing. Decorate cookies, piping lines and dots to resemble snowflakes. To sprinkle certain areas with sugar, but not others, pipe those areas, sprinkle with sugar and let set 5 minutes, tap off sugar, and let set 30 minutes. Continue piping until desired effect is achieved. (Decorated or undecorated cookies can be stored in an airtight container at room temperature up to 3 days. Undecorated cookies can be frozen up to 2 months; let come to room temperature before decorating.)