6 Buttercrunch (or other Bibb-type) lettuce leaves
6 tablespoons hoisin sauce, divided
18 fresh Asian (or Thai) basil leaves
12 fresh mint leaves
6 cooked large shrimp, peeled, deveined, and cut lengthwise in half
1 teaspoon finely chopped peanuts
Plum sauce (optional)
Place noodles in a large bowl; cover with boiling water. Let stand 8 minutes, and drain.
Spread clean, damp kitchen towel on work surface. Add hot water to a large, shallow dish to a depth of 1 inch. Place 1 rice paper sheet in water, and let stand 15 seconds or until soft and pliable. Carefully lift softened rice paper from water and place on towel.
Place 1 lettuce leaf in center of rice paper, leaving 2 inches of paper uncovered on each side. Drizzle lettuce with 1 teaspoon hoisin sauce. Scatter 3 basil leaves and 2 mint leaves over lettuce. Top with ¼ cup rice noodles. Place 2 shrimp halves lengthwise over noodles.
Fold uncovered sides of rice sheet over filling until edges meet in center of roll.
Beginning at one end, roll up jelly-roll fashion, and press seam to seal. Place roll, seam side down, on a serving platter; cover with a damp cloth to keep from drying out. Repeat procedure with remaining rice papers, lettuce, hoisin sauce, basil, mint, rice noodles, and shrimp.
Combine remaining 4 tablespoons hoisin sauce and peanuts.
Cut spring rolls diagonally and crosswise in half; serve with hoisin sauce mixture or purchased plum sauce, if desired.