Prepare the oven and the crust. Preheat your oven to 160°C (140°C fan). Line the base of a 20cm springform tin with parchment paper. Place the digestive biscuits into a food processor and blitz until they resemble fine, sandy breadcrumbs. Add the melted butter and brown sugar, then pulse until the mixture looks like damp sand and holds together when pinched. Tip the mixture into the prepared tin and press it firmly into an even layer using the back of a spoon. You should feel a compact, solid base under your fingers.

Bake the crust. Place the tin on a baking tray and bake the crust for 10 minutes. It will look slightly darker at the edges and smell wonderfully toasty. Remove from the oven and set aside to cool while you make the filling. Leave the oven on.

Make the cheesecake filling. In a large mixing bowl using a stand mixer with the paddle attachment or a hand mixer, beat the room-temperature cream cheese on a low speed until it is completely smooth and glossy, with no lumps at all. This should take about 2 minutes. After that, add the caster sugar and vanilla extract, beating on a low speed again until fully combined—the mixture will look silky and feel light. Scrape down the sides of the bowl with a spatula.

Add the eggs and cream. Add the eggs one at a time, mixing on low speed after each addition until just combined. The batter will become thinner and look velvety. Pour in the double cream and the tablespoon of flour, and mix on low for another 30 seconds until everything is completely homogenous. The filling should be smooth, thick, and pale in colour, with a luscious, pourable consistency.

Assemble and bake. Pour the cheesecake filling over the cooled crust. Gently tap the tin on the counter a few times to release any air bubbles. Place the tin on a baking tray. Place the baking tray on the middle rack of the oven, and then carefully pour about 1cm of boiling water into the baking tray itself (not the cheesecake tin—this creates steam). Bake for 45 minutes. The edges of the cheesecake will look set and pale golden, but the centre should still have a slight wobble when you gently shake the tin. The top will be a very light, matt gold.

Cool and chill. Turn off the oven and leave the cheesecake inside with the door slightly ajar for 1 hour. This gentle cooling prevents cracking. After an hour, remove the cheesecake from the oven and run a thin knife around the edge of the tin to loosen it. Let it come to room temperature completely on a wire rack, then cover and refrigerate for at least 4 hours, but ideally overnight. The texture will be firm, dense, and perfectly sliceable.

Make the caramel pecan topping. About 30 minutes before serving, place the unwrapped caramel toffees, the 60ml of double cream, and a pinch of sea salt flakes in a small saucepan. Warm over a very low heat, stirring constantly, until the toffees have completely melted and the sauce is smooth, glossy, and a deep amber colour. The smell will be rich and buttery. Remove from the heat and stir in the pecan halves until they are fully coated.

Finish and serve. Pour the warm caramel pecan mixture over the top of the chilled cheesecake, spreading it gently to the edges. The sauce will set slightly as it cools, creating a sticky, decadent layer. Slice with a sharp, hot knife for clean cuts.