Step 1

Preheat your oven to 350 degrees F (175 degrees C) and lightly grease a 9-inch springform pan with nonstick cooking spray. Line the bottom of the pan with a round of parchment paper and the sides with one or two strips of parchment.

Step 2

Whisk together the flour, cocoa powder and salt in a bowl. Chop 2 of the chocolate toffee bars into bite-sized pieces and stir into flour mixture.

Step 3

Set a large heatproof bowl over a pot of lightly simmering water. Add the butter and chocolate chips and stir until melted and smooth. Remove from the heat and stir in the brown sugar. Beat in the eggs, one at a time, followed by 1 1/2 teaspoons of the vanilla. Add the flour mixture and stir to combine.

Step 4

Spread the batter into the prepared pan. Bake just until firm, 20 to 25 minutes. Cool completely.

Step 5

For the cheesecake layer, beat the cream cheese in a stand mixer fitted with a paddle or hand mixer on medium-high speed until smooth, about 1 minute. Scrape down the bowl, add in the sugar and remaining 1 1/2 teaspoons vanilla and continue to beat until smooth and creamy, about 2 minutes.

Step 6

Using a hand mixer, whip the cream in a medium bowl to stiff peaks. Fold the whipped cream gently into the cream cheese mixture. Spread evenly over the cooled brownie layer.

Step 7

Finely chop the remaining 2 chocolate toffee bars and sprinkle over the edge of the cheesecake. Place in the fridge to firm up for at least 5 hours or up to 5 days before cutting to serve.