Created by lazyme on September 29, 2019
Step 1: Prepare grill for cooking. If using a charcoal grill, open vents on bottom of grill, then light charcoal. Charcoal fire is medium-hot when you can hold your hand 5 inches above rack for 3 to 4 seconds. If using a gas grill, preheat burners on high, covered, 10 minutes, then reduce heat to moderate.
Step 2: Cut kielbasa crosswise into 4 long sections, then halve each section lengthwise. If using kosher salami, cut lengthwise into 8 (1/4-inch-thick) slices. Trim off skin if desired.
Step 3: Whisk together oil, mustard, horseradish, vinegar, honey, salt, and pepper in a small bowl until emulsified. Toss lettuce with half of vinaigrette and reserve remainder.
Step 4: Grill tops and bottoms of rolls on lightly oiled grill rack, covered only if using a gas grill, turning over once, about 2 minutes total, then transfer, cut sides up, to a platter. Brush cut sides of top halves with remaining vinaigrette and mound salad on bottom halves.
Step 5: Grill sausage on lightly oiled grill rack, covered only if using a gas grill, turning over once, 3 to 4 minutes total, then arrange on top of lettuce (2 pieces per sandwich) and cover with top halves of rolls. Cut sandwiches in half crosswise.
Step 6: Note: Sausage and rolls can be grilled in batches in a hot lightly oiled well-seasoned ridged grill pan over moderately high heat.