Raspberry Jam:

In a small saucepan, combine raspberries and granulated sugar.

Simmer over medium heat until berries break down, mixture thickens, and temperature reaches 106° C / 225° F on a candy thermometer. (If you don’t have a thermometer, you can do a manual test to check for thread stage).

Remove from heat and stir in lemon juice. Refrigerate while you prepare the other components.

Dark Chocolate Brownie:

Preheat oven to 330° F / 165° C. Line an 8×8-inch square baking tin with parchment, allowing a 1-inch overhang on all sides. Spritz lightly with butter or cooking spray. Set aside.

Melt butter in a small saucepan over medium heat.

Whisk in granulated sugar, cocoa powder, and kosher salt. Mixture will be thick and grainy.

Remove from heat and cool slightly, about 5 minutes.

With a rubber spatula, scoop mixture into a large mixing bowl. Add eggs and vanilla and whisk briskly to combine.

Fold in the flour until no dry spots remain.

Fold in the chocolate.

Set aside while you prepare the cream cheese swirl.

Cream Cheese Swirl:

Add softened cream cheese to a large mixing bowl or the bowl of a stand mixer fitted with paddle attachment. Mix on high speed until light and fluffy.

Mix in granulated sugar, egg yolk, and vanilla bean paste, and continue mixing until smooth and creamy.

Assembly:

Spread 2/3 of the brownie batter into prepared tin.

With a teaspoon, drop mounds of cheesecake mixture over the top. Use a knife to swirl cream cheese into brownie batter.

With a teaspoon, drop raspberry jam over the cheesecake, and use a knife to swirl.

To finish, drop spoonfuls of reserved brownie batter over the top.

Bake in preheated oven for 50-60 minutes, or until a toothpick or cake tester comes out mostly clean.

Cool completely in tin. Slice into squares and serve.

Store leftover brownies in an airtight container in the refrigerator for up to 3 days.