Capelli d'angelo con l'erbetta

Serves four
Difficulty - Easy

1/3-cup butter
watercress 2 bunches, leaves and tender tips, washed and very finely chopped
1/2-cup freshly grated Pecorino cheese
salt and freshly ground black pepper
1 lb angel hair, vermicelli or spaghettini works best
6 quarts water

Cook the pasta, reserving 1/4 cup of cooking liquid.
When done, drain lightly, and place in a warm serving bowl, or directly into pan with the melted butter, immediately adding watercress, cheese and several grinds of the pepper mill.
If you prefer the sauce moister, or it seems too dry, add a tablespoon of the reserved liquid at a time till desired moistness is reached.
Mix well and serve immediately onto pre-warmed plates.

I found fresh angel hair the tastiest.