01 - Preheat oven to 350°F. Line a 12-cup muffin tin with paper liners or grease thoroughly.
02 - Melt butter in a medium bowl. Whisk in granulated and brown sugars until glossy. Beat in eggs and vanilla until fully incorporated.
03 - Sift cocoa powder, flour, and salt into the wet mixture. Stir gently until just combined—avoid overmixing to prevent tough texture.
04 - Distribute brownie batter evenly among muffin cups, using approximately 1 heaping tablespoon per cup.
05 - Beat softened cream cheese in a separate bowl until smooth. Add sugar, egg, and vanilla; mix until creamy and free of lumps.
06 - Spoon about 1 tablespoon of cheesecake mixture over each brownie base. Gently smooth tops to create an even layer.
07 - Generously sprinkle each cup with desired toppings: chocolate chips, nuts, crushed Oreos, and mini M&Ms.
08 - Bake for 22 to 25 minutes until cheesecake is set and brownie edges feel firm to the touch.
09 - Let cool in pan for 10 minutes, then transfer to wire rack. Refrigerate at least 1 hour before serving for optimal texture.