How to make a hollandaise sauce
Place the diced shallot, white wine and white wine vinegar in a saucepan. Bring to the boil and allow to reduce. Place the reduction in a bowl with the egg yolks. Place the bowl over a pan of simmering water and whisk over a gentle heat until the mixture triples in volume. Remove from the heat and then whisk in the melted butter, adding a dash of water if the mixture is too thick. Continue whisking until the sauce is smooth and glossy. Season with salt, a squeeze of salt and a pinch of cayenne pepper. Serve with asparagus or salmon.