Chocolate Cheesecake Bars

Heat the oven to 350°F and arrange a rack in the middle.

Cut a 22-inch-long piece of parchment paper and fold over the edges so it measures 8 inches wide; set it aside. Coat an 8-by-8-inch metal baking pan with butter and line it with the parchment seam-side down (the 2 long ends will hang over the edges). Be sure to fit the parchment as smoothly as possible into the pan, snugly creasing it into the corners. Set the pan aside.

Place the flour, 1/4 cup of the sugar, and the almond flour or meal in the bowl of a stand mixer fitted with a paddle attachment and mix on low speed until combined.

Add the measured butter and mix until combined and crumbly, about 2 minutes.

Transfer the mixture to the prepared pan and, using the bottom of a measuring cup dipped in flour, press it firmly and evenly into the pan.

Bake until the crust is golden around the edges and springs back gently to the touch, about 20 minutes. Meanwhile, make the chocolate cheesecake topping.Wash and dry the bowl and paddle of the stand mixer.

Place the cream cheese in the bowl and, using the paddle attachment, beat it on low speed until smooth, about 1 minute.

Add the remaining 2/3 cup of sugar, melted chocolate, eggs, vanilla or almond extract, and salt and beat until combined and smooth, stopping to scrape down the bowl and paddle with a rubber spatula once, about 1 minute total.Return the mixer to low speed, slowly add the cream, and mix until almost completely combined. Increase the speed to medium-low and mix until well combined and smooth, about 1 minute; set aside.When the crust is ready, remove the pan from the oven to a wire rack.

Pour the chocolate cheesecake mixture over the crust (no need for the crust to be cool) and smooth the top.

Bake until the top is just set, about 35 minutes.

Transfer to the wire rack and let sit at room temperature until completely cooled, about 2 hours. (At this point you can slice and serve the bars, but we recommend letting them chill thoroughly in the refrigerator, about 2 hours more, before slicing and serving.) Cover with plastic wrap and refrigerate until ready to serve, up to 3 days.To remove the cheesecake bars from the pan, grip the parchment hanging over the edges and pull it out of the pan.

Transfer to a cutting board, slide out and discard the parchment, and, using a long knife, cut 64 (1-inch) pieces, wiping the knife clean between slices.