Ingredients:
- 1/2 cup (1 stick) Unsalted Butter, melted and cooled slightly
- 1/2 cup Granulated Sugar (for the base)
- 1/4 cup Light Brown Sugar, packed
- 1 Large Egg (for the base), room temperature
- 1 teaspoon Vanilla Extract (for the base)
- 3/4 cup All-Purpose Flour, sifted
- 1/4 cup Unsweetened Cocoa Powder (Dutch-process recommended)
- 1/4 teaspoon Baking Powder
- 1/2 teaspoon Fine Sea Salt (for the base)
- 1/2 cup Semi-Sweet Chocolate Chips
- 16 oz Full-Fat Cream Cheese, room temperature (two 8oz blocks)
- 1/2 cup Granulated Sugar (for the filling)
- 1/4 cup Sour Cream or Crème Fraîche, room temperature
- 1 Large Egg (for the filling), room temperature
- 1 teaspoon Vanilla Extract (for the filling)
- Pinch Fine Sea Salt (for the filling)
Instructions:
- Preheat the oven to 350°F (175°C). Line a 12-cup standard muffin tin with paper liners.
- Melt the butter and allow it to cool for 5 minutes.
- In a mixing bowl, whisk together the melted butter, granulated sugar (base), and brown sugar until smooth. Add the egg (base) and vanilla extract (base); whisk until just combined.
- Sift together the flour, cocoa powder, baking powder, and salt (base) into the wet mixture. Fold gently with a spatula until just combined. Fold in the chocolate chips.
- Scoop about 2 tablespoons of the brookie batter into the base of each muffin liner. Gently press the batter down to form an even, compact layer.
- For the filling, use an electric mixer on low speed to beat the room-temperature cream cheese until smooth and entirely lump-free.
- Gradually beat in the sugar (filling) until smooth. Then mix in the sour cream, vanilla (filling), and salt (filling).
- Beat in the large egg (filling) for only 15–20 seconds on the lowest speed. Stop immediately once the yolk is incorporated to prevent cracking.
- Pour or spoon the cheesecake filling evenly over the brookie base in each cup, filling them almost to the top (leave about 1/4 inch space).
- Bake for 20–25 minutes. The edges should look set, but the centre should still have a slight wobble.
- Turn the oven off, prop the door open slightly, and leave the cups inside for 15 minutes to cool gradually.
- Remove the cups from the oven and transfer them to a wire rack to cool completely to room temperature (about 45 minutes).
- Once cool, cover the muffin tin loosely and refrigerate for a minimum of 2 hours, or ideally 4 hours, before serving.