Step 1

In a small bowl, stir together the lime juice, oil, vinegar, mustard, soy sauce and brown sugar until the sugar dissolves; set aside.

Step 2

Halve, pit and peel the avocados, and then cut them into 1/2-inch dice.

Step 3

Place a wide, shallow bowl of warm water on a work surface. Lay a clean kitchen towel next to the bowl. Dip 1 rice paper round into the water for a few seconds to soften, then lay it flat on the towel. Dip a second round into the water and lay it directly on top of the first one. Using another towel, pat the top of the rice paper dry.

Step 4

Center a lettuce leaf on top of the stacked rice papers. Starting about one-third in from the edge closest to you, arrange a few of the basil and mint leaves in a line across the lettuce. Top with a small row each of the carrot, cucumber and avocado; be careful not to overstuff the roll. Lift the bottom edge of the rice paper up and over the filling and then roll once to form a tight cylinder. Fold in the sides of the rice paper and continue to roll the paper and filling into a tight cylinder. Set aside, seam side down. Repeat with the remaining rice paper and filling ingredients to make 10 rolls.

Step 5

Cut each roll in half crosswise and arrange, cut side up, on a platter. Place the sauce alongside for dipping and serve immediately. Makes 20 rolls; serves 8 to 10.

Step 6

Adapted from Williams-Sonoma New Flavors for Appetizers, by Amy Sherman (Oxmoor House, 2008).