Cook the shrimp in boiling salted water for 2–3 minutes until pink and firm. Drain, cool, and slice each shrimp in half lengthwise.
Prep all filling ingredients: slice avocado, shred lettuce, and julienne vegetables.
Fill a shallow dish with warm water. Dip rice paper in the water for 5 seconds until soft.
Place softened rice paper on a flat surface. Layer vegetables, herbs, shrimp, avocado, and noodles (if using).
Fold the bottom of the rice paper over the filling, tuck in the sides, and roll tightly.
Repeat with remaining rolls.
Whisk all peanut sauce ingredients in a bowl until smooth.