Dressing:
3/4 cup mayonnaise
1/4 cup finely chopped fresh Thai basil leaves
1/4 cup finely chopped fresh cilantro leaves
2 green onions, finely chopped
2 tablespoons fresh lime juice

Patties:
1/4 cup Vietnamese fish sauce (nuoc mam)
4 teaspoons jaggery (palm sugar) or brown sugar
1 teaspoon sriracha or other Asian hot chili sauce
2 pounds freshly ground pork
1/4 cup chunky peanut butter
2 teaspoons grated fresh ginger
2 teaspoons minced garlic
1/2 teaspoon ground star anise
Vegetable oil, for brushing the grill rack
6 French rolls, split
6 interior butter lettuce leaves

Prepare a medium-hot fire in a charcoal grill with a cover, or preheat
a gas grill to medium high.

For the Dressing: combine the mayonnaise, basil, cilantro,
green onions, and lime juice in a bowl. Cover and refrigerate.

For the Patties: combine the fish sauce, jaggery, and chili sauce
in a medium bowl. Add the pork, peanut butter, ginger, garlic, and star
anise and blend loosely with a fork. Form into 6 equal patties the
approximate dimensions of the rolls, making a slight depression in the
middle of the patties to compensate for the tendency to bulge during
cooking.

Brush the grill rack with oil. Grill the patties with the grill top closed
for 4 minutes. Turn and grill until an instant-read thermometer inserted
into the center of the patties registers 160 degrees F, about 4 minutes
longer.

During the last 2 minutes of grilling the patties, place the rolls, cut
side down, on the grill to toast.

To assemble the burgers: spread the roll bottoms with a thin layer of
dressing, followed by a lettuce leaf. Add the patties and top with
generous dollops of the dressing. Add the roll tops.