Firstly, make the caramel. Place the caster sugar and lemon juice into a large thick bottomed saucepan and cook over a medium/high heat until the sugar mets and turns a lovely caramel colour. While the sugar is cooking, place the single cream into a small microwave safe bowl and warm slightly.
Once the caramel has changed colour, carefully add the warm cream before removing the saucepan from the heat and stirring in the cubed salted butter.
Set aside 100g of the caramel and add the milk to the remaining caramel in the saucepan. Place the saucepan over a medium heat and bring the mixture to the boil until the caramel has been completely dissolved in the milk. Allow to cool.
Preheat your oven to 150 degrees and line and grease a 24cm round cake tin.
Beat the egg yolks with the melted butter and fold through the flour and salt before adding the caramel milk a little at a time and beating constantly.
Beat the egg whites in an elective mister until they are still and use a whisk to gently fold them through the cake batter - t's ok if you batter is still lumpy!
Pour the cake batter into the prepared tin and smooth the surface with the back of a knife. Place the cake into oven for 55 minutes to cook. When you remove the cake it will still wobble slightly.
Once the cake had cooled for 20 minutes in the tin, transfer it to the fridge to completely cool for a minimum or 2 hours - or overnight if possible before removing it from it's tin.
Serve the cake straight from the fridge with the caramel you have put aside and some lightly toasted almonds.