Preheat and Prepare: First, preheat your oven to 180°C (160°C fan). Lightly grease a 23cm x 33cm (9x13 inch) baking tray and line it with parchment paper, leaving some overhang on the sides to act as handles for easy removal later.

Create the Base: Carefully unroll one tube of crescent roll dough. The dough will likely be perforated into triangles. Press the perforations together to form a single rectangular sheet. Gently place this sheet into the bottom of your prepared tray, pressing it out to cover the entire base.

Make the Cheesecake Filling: In a large bowl, using a stand mixer or an electric hand mixer, beat the softened cream cheese and 150g of caster sugar together on medium speed until smooth and creamy, about 2-3 minutes. Scrape down the sides of the bowl to ensure everything is well combined.

Add Flavour: Beat in the egg, vanilla extract, and lemon zest (if using) until just combined. Be careful not to overmix at this stage; we just want to incorporate the ingredients without adding too much air. I find that mixing for about 30-45 seconds is plenty.

Assemble the Layers: Pour the cream cheese mixture over the crescent dough base in the tray and spread it evenly with a spatula.

Add the Top Layer: Unroll the second tube of crescent roll dough and press the perforations together, just as you did for the base. Carefully lay this sheet over the cream cheese filling. It doesn't have to be perfect!

Prepare the Topping: In a small bowl, mix together the 50g of caster sugar and the ground cinnamon. Brush the top layer of dough with the melted butter, then sprinkle the cinnamon-sugar mixture evenly over the top.

Bake to Perfection: Place the tray in the preheated oven and bake for 30-35 minutes, or until the top is a deep golden brown and the filling is set. A good visual cue is that the centre will look firm and not wobble excessively when the tray is gently shaken.

Cool Completely: This is a crucial step! Remove the tray from the oven and let it cool on a wire rack to room temperature, which will take at least one hour. For the cleanest cuts, I recommend then chilling the entire tray in the refrigerator for at least 2-3 hours, or even overnight. Once chilled, use the parchment paper handles to lift the cheesecake from the tray and slice it into 12 bars.