Preheat the oven to 350°F (175°C) and grease a heart-shaped baking pan.

In a bowl, combine melted butter and cocoa powder until smooth. Stir in sugar, then add eggs one by one, mixing well after each addition. Fold in flour until just combined.

In another bowl, beat cream cheese until smooth; mix in sugar and vanilla extract.

In a small saucepan, heat raspberries over low heat until softened; mash slightly.

Pour half of the brownie batter into the prepared pan. Add dollops of cheesecake batter on top, then pour in remaining brownie batter and drizzle with raspberry sauce. Swirl gently with a knife.

Bake for 25-30 minutes or until a toothpick comes out clean. Let cool before cutting into heart shapes.