Step 1

In a medium bowl, whisk together flour, baking soda, salt, and spices.

Step 2

In the bowl of a stand mixer fitted with the paddle attachment, beat together butter and sugars on medium speed until light and fluffy, 2 minutes. Reduce speed to low; beat in half the flour mixture. Beat in milk, followed by remaining flour mixture. Shape dough into a flat disk, wrap in plastic, and refrigerate until firm, at least 2 hours or up to overnight.

Step 3

Line three baking sheets with parchment. Dab speculaas mold all over with a small piece of dough (this provides a light buttery coating that prevents sticking). Generously sprinkle mold with flour, tapping to remove excess. Take a piece of dough that is roughly the same size as the mold; using your palm, press into mold. Using a long, thin knife, scrape off excess dough. Invert mold over a prepared baking sheet; rap far end of the mold against the sheet, holding it at an angle to release the formed cookie. Sprinkle mold with more flour; repeat with remaining dough. Gather scraps (refrigerate if dough gets too soft) and form more cookies. Freeze at least 30 minutes.

Step 4

Preheat oven to 350 degrees. Bake until firm and golden, 15 to 20 minutes. Transfer parchment with cookies to wire racks; let cool completely.