Makes 24 Slices
½ cup (1 stick) butter, plus a little extra for the pan
3 cups unbleached all-purpose flour
2 teaspoons baking soda
1½ teaspoons baking powder
½ teaspoon salt
2 teaspoons cinnamon
1 tablespoon powdered ginger
½ teaspoon ground cloves
3 tablespoons (3 to 4 ounces) grated fresh ginger
2/3 cup (packed) brown sugar
¾ cup molasses
2 large eggs
2 teaspoons pure vanilla extract
1½ cups buttermilk
Step 1 – Slice butter into cubes and allow to soften prior to cooking.
Step 2 – Adjust the oven rack to the centre position and preheat the oven to 350°F (325°F if you’re using a glass pan). Put a little soft butter on a paper towel, a piece of waxed paper, or a butter wrapper, and lightly grease the bottom and corners of a 9-by 13-inch pan. (No need to grease the sides.)
Step 3 – Combine the flour, baking soda, baking powder, salt, cinnamon, powdered ginger, and cloves in a medium-sized bowl. Whisk slowly to blend, and then stir in the grated fresh ginger, whisking until it’s distributed. Set this aside.
Step 4 – Crumble the brown sugar into the bowl with the softened butter. Use a handheld electric mixer at high speed (or if you don’t have one, use a whisk, with enthusiasm) to beat the butter and sugar together until light and fluffy. Add the molasses and then the eggs, one at a time, beating well after each addition. Use a rubber spatula to scrape the sides of the bowl a few times during this process. Add the vanilla extract, and continue to beat for another minute or two, until everything is well combined.
Step 5 – Add about a third of the flour mixture to the butter mixture, slowly whisking just enough to mostly blend. Then pour in approximately a third of the buttermilk, and stir it in. Continue with another third of the flour mixture, and another third of the buttermilk. Then repeat with the remaining flour mixture and buttermilk. As you do this, switch to stirring with a spoon when the batter thickens, and mix from the bottom of the bowl after each addition—just enough to thoroughly blend without overmixing. (It’s okay if the finished batter is not completely smooth.)
Step 6 – Transfer the batter to the prepared pan, taking care to scrape all of it in with a rubber spatula. Then use the spatula to spread the batter evenly. Bake for 35 to 40 minutes, or until the top is springy to the touch and/or a toothpick inserted all the way into the center comes out clean.
Step 7 – Remove the pan from the oven and allow the gingerbread to cool in the pan for at least 15 minutes before cutting it into 24 rectangular pieces. Serve warm, at room temperature, or cold.