Prepare the Patties
In a medium-sized mixing bowl, combine the finely chopped peanuts, green onions, curry powder, freshly ground black pepper, water, oyster sauce, and fish sauce. Add the ground beef and mix thoroughly using your fingers. If not cooking immediately, cover and refrigerate for up to 24 hours. Form the mixture into 24 patties, each approximately 2 inches wide and 1/2 inch thick. Set aside.
Make the Nuoc Cham Sauce
In a small bowl, mix 2 tablespoons of sugar (or 3 tablespoons of maple syrup) with 3 tablespoons of lime juice and the water. Taste and adjust the limeade, adding the remaining sugar or lime juice if necessary, and additional water if too concentrated. For a smoother flavor, add vinegar if the mixture is overly tart or bitter. Incorporate the fish sauce to taste, aiming for a bold finish that will complement the lettuce and herbs. For additional flavor, include thinly sliced chiles, garlic, or carrot, keeping the chiles optional for diners sensitive to heat. This sauce can be kept at room temperature for up to 8 hours until ready to serve.
Cook the Noodles
Bring a large pot of unsalted water to a boil, add the noodles, and return to a boil. Cook until tender with a slight chewiness (timing can vary from 2 to 8 minutes; testing a strand is recommended). Drain, rinse under cold water, drain once more, and allow to cool for about 5 minutes. Arrange the noodles in 2-inch nests on a plate or in a shallow bowl. Place on the table along with the dipping sauce, lettuce, and fresh herbs.
Cook the Beef Patties
Lightly oil a cast-iron grill pan or film a heavy skillet with oil. Place over medium-high heat. In batches, cook the patties for 4 to 5 minutes, turning halfway, until they reach medium to medium-well doneness. (For a more rare option, reduce the cooking time if preferred.) Transfer to a platter and allow to cool slightly.
Serve
Invite diners to assemble their own wraps with lettuce, herbs, noodles, and beef patties. For ease, break or cut each patty into bite-size pieces. Offer the sauce on the side for individual dipping or portion it into small bowls before serving.