Trim the toughest end of the asparagus and peel the bottom third if the asparagus are tough. Cut spears in half.
Bring water to a boil in a 2-quart or larger pan. Add salt and asparagus. Cook for up to 3 minutes. Remove from water while spears are still bright green and plunge into cold water.
Coat bottom of a skillet with preferred fat or oil and saute the leeks on medium heat. As they soften, add garlic and dandelion greens and cook until greens are wilted. Remove from heat. Toss in blanched asparagus, vinegar and season to taste.