• Preheat oven to 350°F / 180°C and spray brownie bites pan lightly with cooking spray (if you aren't using the brownie bites pan, see post above for what to use instead)
• Sieve all the dry ingredients for the cake into a bowl
• Add the egg, vegetable oil, milk and vanilla and stir until everything is smooth and combined
• Add the hot water and mix in - the batter will be very liquid
• Pour the batter into the brownie pan, fill the cavities about ¾ full
• Bake for 15 minutes or until a skewer inserted comes out clean
• Allow to cool in the pan for about 30 minutes before trying to remove

Make the Caramel

• Put the sugar and water in a saucepan over a medium-low heat
• Don't stir the sugar, just let it melt and dissolve into the water. Once it has completely dissolved, keep stirring until it starts to turn a light amber colour, then add the butter
• Once the butter has melted, keep cooking, stirring constantly for about a minute
• Slowly pour in the cream, stirring constantly - the mixture will bubble up and might spit a little, so be careful
• Once the cream is fully incorporated, check the colour of your caramel. If you are happy with the colour, remove it from the heat. If you want it darker, keep going until it is how you like it - don't leave it unattended though, as it can burn very quickly!
• Allow it to cool and thicken a little before trying to put it into the chocolate squares - use a spoon or piping bag to put a small amount on there, just until it fills up, then gently tap the square on your worktop to tease it into the corners
• Sprinkle with sea salt and leave to set