Eggnog Caramel Brownies

Make the eggnog caramel: In a small saucepan, heat the sugar and water over medium-high heat, swirling it often to dissolve the sugar, until the sugar melts and turns into a fully liquid golden-brown caramel. Remove the pan from the heat and whisk in the butter until it emulsifies with the sugar and is smooth. Pour in the cream and whisk until smooth. Stir in the nutmeg, cloves and salt, followed by the rum and vanilla. Transfer the caramel sauce to a bowl and let stand until cool to the touch. Whisk in the egg yolks, then refrigerate the caramel sauce until cold and thickened, at least 1 hour. You can prepare this caramel sauce up to three days ahead of time.

Heat the oven to 350 degrees. Grease a 9-by-13-inch metal baking pan with baking spray, then line the bottom and two long sides with a sheet of parchment paper, cut to fit so it lies perfectly flat in the pan. Bend the excess parchment paper over the edges of the pan. If using metal binder clips, fasten the parchment to the edges of the pan (see Essential Bar Cookie Equipment).

Make the brownie batter: In a large heatproof bowl, combine the butter and chocolate. Place the bowl over a saucepan of simmering water (do not let the bottom of the bowl touch the water) or use a microwave and heat until the butter and chocolate are melted. Remove the bowl from the saucepan or microwave and whisk in both sugars, the vanilla, salt and, lastly, the eggs, whisking until smooth. Stir in the flour and baking powder until just combined, then add the white chocolate chips and fold to combine. Scrape the batter into the prepared pan and spread evenly over the bottom.

Pour the caramel sauce over the brownie batter in four lengthwise rows. Using the tip of a dinner knife, swirl the caramel into the batter; don’t swirl too much, you want some bigger blobs along with some swirls. Bake until the brownies are set and a toothpick inserted in the center — avoiding any pockets of caramel — comes out with a few crumbs attached, 50 to 55 minutes.

Transfer the pan to a wire rack, and while it’s still hot, scatter the brownie slab liberally with white and gold sprinkles. Let cool completely.

Using the overhanging parchment paper like a sling, lift the brownie slab from the pan and transfer it to a cutting board; slide out and discard the parchment. Cut the brownies into 3 lengthwise rows by 8 crosswise columns to make 24 bars.