Break the asparagus to remove the tough stem and then peel the remaining stalk. Keep the tip intact.
To cook the asparagus: Bring a large saucepan of salted water to the boil and then add the peeled asparagus. Blanch for 2-4 minutes until the asparagus are tender but still have a bit of crunch in the centre.
Firstly clarify the butter. Melt the butter in a saucepan over a low heat to allow the milk solids to separate from the fat. Skim off any foam that comes to the surface and then pour the clear clarified butter into a container, leaving the milk solids in the pan.
Peel and finely chop the shallot. Place in a saucepan with the white wine, thyme and white wine vinegar. Reduce over a medium heat and reduce until you have approximately 100ml of liquid. Pass through a fine sieve.
Place the egg yolks in a heatproof bowl, add the white wine reduction and season with salt. Place the bowl over a pan of simmering water and whisk vigorously until you have a fluffy sabayon. Cook until the mixture reaches the ribbon stage. Remove from the heat and whisk in the clarified butter a little at a time. Check the seasoning and add a couple of drops of lemon juice. Keep warm.
Season the asparagus with Maldon sea salt and serve with the Hollandaise sauce.
«Keep the pieces of asparagus stalk and peelings that you remove to make an asparagus soup.»