1-Preheat oven to 350°F (175°C). Place rack in the center and line a 9×13-inch pan with parchment paper, leaving overhang on the sides for easy removal.

2-Whisk together 2 and 1/4 cups all-purpose flour, 1 and 1/2 teaspoons baking soda, 2 teaspoons ground ginger, 1 teaspoon ground cinnamon, 1/4 teaspoon ground allspice, 1/4 teaspoon ground cloves, 1/4 teaspoon ground nutmeg, a small pinch of ground black pepper, and 1/4 teaspoon salt in a large bowl.

3-In a separate bowl, whisk 3/4 cup melted unsalted butter, 1/2 cup packed light or dark brown sugar, 1/2 cup granulated sugar, and 1/3 cup unsulphured molasses until smooth. Add 1 large egg at room temperature and 1 teaspoon pure vanilla extract; mix well.

4-Combine the wet and dry ingredients until no flour remains; the dough will be thick and shiny. Press the dough evenly into the prepared pan in a thin layer.

5-Bake for 23 26 minutes until the top is set but soft; a toothpick should come out with a few moist crumbs. Avoid over-baking to keep the bars tender. Cool in the pan for at least 1 hour.

6-For the frosting, beat 6 ounces softened full-fat brick cream cheese and 2 tablespoons unsalted butter until smooth. Add 1 and 1/2 cups confectioners’ sugar, 1 teaspoon pure vanilla extract, and a small pinch each of ground ginger, cinnamon, and allspice; beat until creamy. Adjust salt to taste, then spread over the cooled bars. Add sprinkles if desired and refrigerate for 30 minutes.

7-Lift the bars using the parchment overhang and cut into 18 24 squares.