Preheat the oven to 350 degrees.

In a large bowl, combine the brown sugar and flour. Add the butter and using a pastry cutter (or a food processor), cut the butter into the flour and mix until you have a fine crumb mixture. Press into the bottom of a 9” square pan that’s been lined with parchment paper and sprayed with cooking spray. Place in the oven and bake for about 20 minutes until the crust is golden. Remove and let cool completely.

In a large bowl, using an electric mixer, beat the cream cheese and sugar together until light and fluffy. Add in the egg and beat until combined. Add in the vanilla and sour cream and mix. Pour over the crust in an even layer.

In a small bowl, mix the nutella and heavy cream until smooth. Drizzle over the top of the cream cheese layer and using a skewer, swirl the nutella and cream cheese layer together, taking care not to drag too deep and hit the crust. Place in the oven and bake for 30 minutes until set. Remove and allow to fully cooled, even better to allow to chill in the refrigerator for 2-3 hours. Slice and serve.

Store any leftovers in an airtight container in the refrigerator for up to 3 days.