Cream the butter and sugar. Using a hand mixer or stand mixer, cream the butter and brown sugar in a large bowl until light and fluffy, about 2 minutes.
Add the molasses, egg, and vanilla. Beat in the molasses, egg, and vanilla until fully combined.
Whisk the dry ingredients. Meanwhile, in a separate bowl, whisk the flour, baking soda, salt, cinnamon, ginger, nutmeg, allspice, and cornstarch.
Combine the dry and wet ingredients. Add the dry ingredients to the wet and mix with the mixer until a soft, slightly sticky dough forms.
Refrigerate. Cover the dough with plastic wrap and refrigerate for 30–60 minutes to help it firm and prevent excess spreading.
Prep the oven and baking sheets. Preheat the oven to 350°F. Line two baking sheets with parchment paper.
Shape the cookies. Scoop out 1½ tablespoons of dough for each cookie. Roll the dough into balls, then roll them in granulated sugar before transferring them to the baking sheet.
Bake. Transfer the baking sheet to the oven and bake the gingerbread cookies for 9–11 minutes, or until the edges are set and the centers are still slightly soft.
Let them cool. Remove the cookies from the oven and let them cool on the baking sheet for 5 minutes, then transfer to a wire rack. If any cookies bake slightly unevenly, use a round cookie cutter or a small bowl to scoot them into a perfect circle while they are still warm.
Melt the chocolate and decorate the cookies. Melt the wafers according to package instructions. Dip half of each cooled cookie into the melted white chocolate and place on parchment to set. Add sprinkles while still wet.
Serve. Once the chocolate is set, serve your gingerbread cookies or store them for later.
Notes
Cornstarch helps the cookies stay extra soft and tender. You can leave it out for a slightly firmer, classic texture.
Chocolate melting wafers melt smoothly without additional oil. If substituting white chocolate chips, add ½ to 1 teaspoon of vegetable oil to help thin them out. White chocolate bars melt well, too. The cookies taste delicious undipped as well. They are soft, flavorful, and delicious on their own.
Melt the chocolate in the microwave in 15-second intervals, stirring well between intervals. Add a touch of oil only when needed.
Pull the cookies from the oven while the centers still look slightly underdone. They will finish setting as they cool.
If you want perfectly round cookies, you can scoop them inside a round cookie cutter while they are still warm.
Freeze baked cookies (plain or dipped) for up to 3 months.
To freeze the unbaked cookie dough balls: First, freeze them on a baking sheet, then transfer to a freezer bag and freeze for 3 months. Bake from frozen and add 1-2 minutes to the bake time.