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 combined.
03 - Sift cocoa powder, flour, and salt into the wet mixture. Stir until just combined—avoid overmixing.
04 - Distribute brownie batter evenly among prepared muffin cups, using about 1 heaping tablespoon per cup.
05 - Beat cream cheese until smooth in a separate bowl. Add sugar, egg, and vanilla. Mix until creamy and lump-free.
06 - Spoon approximately 1 tablespoon of cheesecake mixture over each brownie base. Gently smooth tops.
07 - Generously sprinkle each cup with chocolate chips, nuts, crushed Oreos, and M&Ms.
08 - Bake for 22–25 minutes until cheesecake is set and brownie edges are firm.
09 - Cool in pan for 10 minutes. Transfer to wire rack to cool completely. Refrigerate at least 1 hour before serving.