Step 1: Prepare all your fillings. Cook vermicelli noodles according to package directions, rinse with cold water, and drain well. Cook and slice your protein (shrimp, chicken, or tofu). Julienne cucumber, carrot, and bell pepper. Shred lettuce/cabbage. Wash and pat dry all fresh herbs.
Step 2: Prepare the peanut dipping sauce. In a small bowl, whisk together the peanut butter, soy sauce, lime juice, honey/maple syrup, rice vinegar, minced garlic, and grated ginger. Gradually add warm water, 1 tablespoon at a time, until the sauce reaches your desired consistency (thick but pourable). Add red pepper flakes if desired. Taste and adjust seasonings.
Step 3: Set up your rolling station. Fill a large shallow dish (like a pie plate) with warm water. Have your prepped fillings, herbs, noodles, and the peanut sauce nearby. Place a clean, damp kitchen towel or a non-stick cutting board on your work surface for rolling.
Step 4: Dip one rice paper wrapper into the warm water for 15-20 seconds, until it is pliable but still slightly firm. Do not oversoak. Gently lift the wrapper from the water, allowing excess water to drip off.
Step 5: Carefully lay the softened wrapper flat on your damp work surface. Arrange a small amount of vermicelli noodles, lettuce, cucumber, carrot, bell pepper, and fresh herbs horizontally across the bottom third of the wrapper, leaving about an inch clear on each side.
Step 6: If using shrimp, place 2-3 halves face down (pink side visible) near the top edge of the filling stack, just before you start rolling. If using chicken or tofu, add it with the other fillings.
Step 7: Fold the bottom edge of the rice paper up and over the fillings, tucking it in snugly. Then, fold in the left and right sides towards the center. Tightly roll the wrapper upwards from the bottom, away from you, until you reach the top, creating a secure roll.
Step 8: Place the finished roll on a plate lined with damp paper towels or a serving platter, ensuring they don't touch if possible to prevent sticking. Repeat with the remaining wrappers and fillings. Serve immediately with the peanut dipping sauce. If storing, cover tightly with damp paper towels and plastic wrap for a few hours in the refrigerator, but they are best eaten fresh.