For the brownies
1/3 cup Dutch-processed cocoa
1/2 cup plus 2 tablespoons boiling water
2 ounces unsweetened chocolate, finely chopped
4 tablespoons (1/2 stick) unsalted butter, melted
1/2 cup plus 2 tablespoons vegetable oil
2 large eggs
2 large egg yolks
2 teaspoons vanilla extract
2 1/2 cups sugar
1 3/4 cups unbleached all-purpose flour
3/4 teaspoon table salt
For the cheesecake layer
12-oz cream cheese (1 1/2 half packages), room temperature
1/2 cup sugar
1 large egg
1 tsp vanilla extract
3/4 cup raspberry preserves/jam
Preheat oven to 350F. Make a foil sling for your 13 x 9 inch pan. Spray with nonstick cooking spray.
Whisk cocoa and boiling water together in large bowl until smooth. Add unsweetened chocolate and whisk until chocolate is melted. Whisk in melted butter and oil. Add eggs, yolks, and vanilla and continue to whisk until smooth and homogeneous. Whisk in sugar until fully incorporated. Add flour and salt and mix with rubber spatula until combined. Pour into prepared pan and prepare cheesecake mixture.
In a medium bowl, beat cream cheese, sugar, egg and vanilla extract until smooth. Drop in dollops onto prepared brownie batter. Drop dollops of raspberry preserves into the cheesecake batter. Gently swirl batters with a butter knife, giving the brownies a swirly look.
Bake for 35-40 minutes, until brownies and cheesecake are set. A knife inserted into the cheesecake mixture should come out clean and the edges will be lightly browned. Cool in the pan completely before slicing and serving, either at room temperature or chilled.