The apples will need a really good scrub in hot water with a clean scourer to get rid of any wax. If you omit this step you may find the caramel will just slide off the apple.
You will need
9 assorted apples, room temperature
120g golden syrup
120g double cream, room temperature
Flaky sea salt, such as Maldon, for pressing
1. Combine sugar and golden syrup in a medium heavy-bottomed saucepan, and stir. Cover, and cook over medium-high heat until sugar melts. Uncover, and continue to cook, swirling occasionally, until mixture is dark golden, about 10 minutes.
2. Slowly drizzle in double cream. Remove from heat, and stir until smooth.
3. Let stand 3 minutes to allow caramel to thicken slightly, then dip bottom of 1 apple to test if caramel is thick enough. If most of the caramel runs off of apple, let caramel cool 1 to 2 minutes more, and then try again.
4. Dip apples, 1 at a time, into caramel to coat three-quarters of each apple. Let excess drip off, and scrape bottom of apples against the side of bowl (if caramel begins to harden, reheat over a pot of simmering water).
5. Immediately after coating each apple, transfer each apple to a baking sheet lined with parchment or a non-stick baking mat and sprinkle each apple with salt flakes. Allow to set in the fridge. Preferably overnight.