Halve the chili pepper, remove the seeds if necessary, and cut the chili into thin strips. Peel and finely dice the garlic. Clean and finely dice the mushrooms, and wash and thinly slice the spring onion.

Trim the woody ends off the lemongrass and remove the outer, dry leaves. Halve the inner, lighter, and softer part lengthwise and finely chop it.

Briefly sauté garlic and lemongrass in a pan with oil. Add the ground meat, break it up with a wooden spoon, and fry for four to five minutes until crumbly.

Once the ground beef is nicely crumbled, add the spring onions and mushrooms and sauté for two to three minutes. Season with soy sauce, peanut butter, and pepper. Remove from the heat and set aside briefly.

Peel the carrot and cut it into thin sticks. Wash the lettuce, spin it dry, and chop it into smaller pieces. Place the rice noodles in a bowl, pour boiling water over them, and let them soak for five to ten minutes, then drain the water.

Mix all the sauce ingredients together in a bowl until creamy. Gradually add water until the sauce reaches the desired consistency.

Fill a sufficiently large container with water. Briefly dip the rice paper in it (about three seconds). Place some lettuce, about two tablespoons of the minced meat filling, a few carrot sticks, rice noodles, and a few leaves of fresh mint or cilantro in the center of the rice paper. Fold the bottom of the rice paper over the filling, fold in the sides, and tightly roll up the spring rolls.