Adjust the oven rack to the lower-third position and preheat the oven to 350?F (177?C). Line the bottom and sides of a 9-inch square or 11?7-inch baking pan with parchment paper, leaving an overhang on the sides.

Make the brownie batter: Melt the butter in a large heatproof bowl. Whisk in the oil and granulated sugar, let sit for 3?5 minutes. Whisk in the eggs and vanilla extract. Add the cocoa powder, flour, and salt and whisk until combined. Fold in the chocolate chips. Spread most of the brownie batter into the prepared pan, reserving about 1/2 cup for the top.

Make the cheesecake batter: Beat the cream cheese and granulated sugar together in a large bowl until smooth. Beat in the flour, egg yolk, and raspberry preserves. If desired, add food coloring.

Drop spoonfuls of the cream cheese batter on top of the brownie batter. Spoon the remaining brownie batter on top. Use a knife to create a swirl pattern. Press raspberries into the top, if desired.

Bake for 40?42 minutes or until a toothpick inserted in the center comes out with a few moist crumbs. Tent with aluminum foil after about 25 minutes to prevent over-browning. Remove from the oven and cool completely, at least 3 hours.

Lift the brownies out using the parchment paper overhang and cut into squares.