Steam asparagus in salted water until just tender and bright green; drain, rinse with cold water and drain again.

Place cooked asparagus in the oven to keep warm.

Remove the mint leaves from the stems (reseve; finely chop the leaves and set aside.

In a small saucepan combine mint stems, tarragon, parsley, shallots, white wine and vinegar, bring to a boil and then reduce heat simmering until reduced by half.

Add cream, bring to a boil, reduce heat and simmer again until reduced to 2 Tablespoons of liquid.

Strain the herbed liquid into a double boiler (discard the herbs), beat in the egg yolk and heat over simmering water.

Cut the frozen butter into 12 pieces, and add one piece at a time whisking in each addition until completely melted before adding the next.

Once all butter has been added and the mixture is thickend, stir in the chopped mint leaves and pour over the asparagus