Combine the dipping sauce ingredients in a small bowl. Set aside.
Cook the rice noodles in boiling water according to the package directions. Drain the noodles.
Place the cooked rice noodles into a mixing bowl and add 2 tablespoons of the dipping sauce. Stir until the noodles are coated. Set aside.
Fill a pie plate with hot water. Dip a spring roll skin into the water until it just beings to soften. (Do not allow it to sit in the water too long or it'll get mushy.)
Lay the skin out on a plate. Assemble the spring roll by placing a basil lead in the center of the skin. Next add a layer of noodles, carrots, cucumber, chicken, and top with the avocado slices. (Use about 1/8 of each ingredient per roll.)
To roll the spring roll, fold the back end of the spring roll over the filling. Then fold the two sides into the center. Tightly roll the spring roll up and let the end seal itself to the roll. Repeat with the remaining ingredients.
Serve immediately with the rest of the dipping sauce.
Notes
You want vermicelli-style rice noodles. They're the thinnest of all the rice noodles. The pad Thai/flat rice noodles are too bulky for the spring rolls.