• Preheat the oven to 170°C (150°C fan)/340°F/Gas mark 3½ and line a 20cm (8in) square baking tin with nonstick baking paper.
• Put the white chocolate and butter into a microwave-safe bowl and microwave on low in 30-second bursts, stirring at each interval, until smooth and runny. If you overheat the mixture it can become lumpy or burn. Leave to cool for 10 minutes while you continue with the next steps.
• In a large mixing bowl, beat the eggs with an electric hand mixer until light and foamy (this can take 5–10 minutes), then beat in the sugar, vanilla extract, lemon juice or white vinegar, and red food colouring until combined. Pour in the white chocolate mixture and beat until completely combined. It should look a vibrant pinky-red. If not, add more food colouring.
• Sift in the flour, cocoa powder and salt, then fold in with a wooden spoon or rubber spatula. Scoop three quarters of the batter into your prepared tin and smooth it out to the edges.

For the cheesecake swirl:

• In a medium bowl, use an electric hand mixer or balloon whisk to mix the cream cheese, sugar, egg and vanilla until just combined. Make sure you don’t overmix or it’ll become runny.

To assemble:

• Scoop the cheesecake onto the brownie and smooth it out to the edges, then dollop the rest of the brownie batter randomly on top and swirl it through the cheesecake mix with a knife.
• Bake for 25–30 minutes until the top no longer looks wet, the edges are slightly cracked and the middle wobbles very slightly.
• Leave to cool completely in the tin, then chill in the refrigerator for at least 2 hours or overnight. Cut into 16 squares and enjoy!
• Store in an airtight container in the refrigerator for up to 5 days.

Adapted from: Baked in One: 100 desserts using just one tin