Heat half the oil in a pan and fry the asparagus until tender. Remove and place on kitchen paper to drain excess oil and allow to cool.
Peel and slice the potatoes finely (1mm) and fry in the remaining oil.
Finely puree half of the asparagus with the 4 yolks, garlic, vinegar -- adding the water very slowly.
Chop the egg whites very finely and add to the puree, along with the remaining asparagus and potatoes.
Add the wine, parsley and salt to taste.
Serve chilled.
Ingredients (for 4 persons)