Hollandaise sauce

About 30 minutes before making the sauce, take 150 g of butter from the fridge. Cut the butter into small cubes and allow it to come to room temperature. Pour 5 cm of hot water into the inner pan of your slow-cooker and put the lid on. Put the slow-cooker on HIGH. Put 3 tbsp white wine vinegar, 4 black peppercorns, 1 mace leaf and 1 bay leaf in a saucepan. Let it boil until there is 1 tbsp of the liquid left.

Take a bowl that fits into the inner pan. Beat 3 egg yolks, 1 tbsp butter and a pinch of salt in this bowl. Sieve in the vinegar. Place the bowl in the inner pan and pour in enough boiling water so that the water reaches halfway up the bowl. Whisk for about 3 minutes until the sauce thickens. Take your time for the sauce, as it may clump if you add the butter too quickly. Whisk the remaining butter through the sauce little by little and only add the next quantity when the previous quantity has been completely absorbed. This way, the sauce will gradually thicken. Add salt and pepper to taste. Put the slow-cooker on LOW and keep the sauce warm for 1 hour.