Dice butter and melt slowly in a pot. Bring butter to the boil, simmer for 1-2 minutes and skim off the foam. Remove butter from the stove and let it stand for 2-3 minutes, then skim off the clear butterfat
Crush some pepper. Peel and finely dice the shallots. Bring white wine, bay leaf and pepper to the boil in a saucepan and reduce to about 125 ml for about 5 minutes. Remove the reduction from the stove, pour through a fine sieve and allow to cool
Whisk egg yolks and white wine reduction, season with a little salt and sugar. Beat the egg yolk mixture in a bowl over a hot water bath until foamy. Gradually fold in liquid butter slowly. Season sauce with sugar, salt and lemon juice. Asparagus tastes good with it