In a skillet or frying pan, heat the vegetable oil over medium heat.
Add the minced garlic and sauté for about 1 minute until fragrant.
Add the chopped onion and continue to cook until translucent, about 3 minutes.
Add the ground beef to the pan, breaking it up with a spatula. Cook until browned, approximately 5-7 minutes.
Stir in the fish sauce, soy sauce, sugar, bell pepper, and fresh basil. Cook for another 2-3 minutes until the bell peppers are slightly tender and the basil has wilted. Remove from heat.
Prepare a shallow dish with warm water. Dip one rice paper sheet into the water for 10-15 seconds until it becomes pliable.
Lay the softened rice paper on a flat surface. Place lettuce leaves or a small handful of vermicelli noodles in the center, followed by a few spoonfuls of the beef mixture.
Fold the sides of the rice paper over the filling, then roll from the bottom to the top to form a tight roll. Repeat with remaining ingredients.
Serve immediately with your choice of dipping sauce.