Ravioli with Spring Vegetable Purée

Ingredients

 * Aromatic White Sauce
 * 10 asparagus spears
 * 1 large artichoke
 * 1 bunch scallions or 1 small leek (white part only), chopped
 * 1 tbsp unsalted butter plus more to taste
 * 1 tbsp chopped fresh parsley or chervil
 * 1 fresh thyme sprig or pinch of dried
 * pinch of salt
 * ½ cup fresh shelled or frozen peas
 * freshly ground black pepper
 * 32 wonton skins
 * fresh basil leaves, cut into fine strips for garnish
 * freshly grated Parmesan cheese

Directions

 * 1) Prepare white sauce and set aside.
 * 2) Snap asparagus spears and discard tough ends. Roughly chop stalks and tips and set aside.
 * 3) Break off tough outer leaves of artichoke and discard. Slice off top two-thirds of remaining leaves and trim edges.
 * 4) Cut artichoke into quarters and, using paring knife, cut away fuzzy choke.
 * 5) Roughly chop artichoke.
 * 6) In large saucepan, combine asparagus, artichoke, scallions, potato, 1 tbsp butter, parsley, thyme, salt and ½ cup water.
 * 7) Bring to boil over high heat, then reduce heat to low, partially cover and simmer until vegetables are tender, about 25 minutes.
 * 8) Add peas and cook until tender, about 3 minutes. The water should be evaporated by this time.
 * 9) Transfer vegetable mixture to food processor or food mill and purée until smooth.
 * 10) Stir in additional butter to taste and season with salt and pepper. Purée should not be watery. If it is, return to saucepan and cook over low heat, stirring constantly, until excess moisture cooks away.
 * 11) Cool completely.
 * 12) Lightly dust baking sheet with flour.
 * 13) Lay 16 wonton skins on work surface. Pile 2 tsp filling in center of each square.
 * 14) Using pastry brush dipped in water, paint thin film of water around edge of each wonton square.
 * 15) Lay second square on top and gently stretch it over filling.
 * 16) Press edges together tightly, forcing out all air, then run ravioli crimper around edges to seal tightly.
 * 17) Place on prepared baking sheet. (if holding for more than 1 hour, cover with plastic wrap; chill until ready to cook.)
 * 18) To cook ravioli, bring large saucepan of lightly salted water to boil over high heat. Adjust heat so water is at a gentle boil.
 * 19) Add ravioli and cook until they float to surface (taste test), 3 to 5 minutes.
 * 20) Meanwhile, rewarm white sauce.
 * 21) Using slotted spoon, lift out ravioli, add to sauce, and move pan back and forth to coat.
 * 22) Serve with a sprinkling of pepper, basil and Parmesan.