Step 1: In a large mixing bowl, combine the veal, scallions, garlic, ginger, chile, cilantro, kaffir lime leaf or basil, fish sauce, cumin, coriander, and pepper. Wet your hands with cold water and mix well with your fingers.
Step 2: Divide the meat mixture into 8 equal portions and form into patties. Use the back of a teaspoon or your thumbs to make a shallow depression in one side of each burger. (This helps prevent the burgers from puffing up in the center as they cook.) Place on a plate lined with plastic wrap; cover with more plastic wrap and chill until ready to cook. The slider patties can be made several hours ahead.
Step 3: Set up the grill for direct grilling and preheat to high. Brush and oil the grill grate.
Step 4: Arrange the burgers, depression side down, on the grate. Grill, turning once, until cooked to an internal temperature of 160 degrees, 3 to 4 minutes per side. (Insert the probe of an instant-read thermometer through the side of the burger.) Grill the cut sides of the rolls on until browned, 30 seconds; watch carefully.
Step 5: To assemble the sliders, place a burger on each toasted roll. Top with peanut sauce, cucumber, carrot, and cilantro sprigs. Dig in!