Simply rub some salt, sugar and pepper over two salmon fillets and sandwich them together with some dill in between.
Some recipes also recommend a splash of spirits, such as brandy, gin or lemon vodka. Either way, put a plate on top with some weight on it and let it sit in the fridge for two to three days, basting as you go.
To serve, a squeeze of lemon and some dark bread will work well; mustard sauce if you want to do a little extra work. Drink enough Champagne with it and at least your insides will be warm.