Place buns on hot grill, cut side down, and grill until toasted, 1-2 minutes.
Transfer grill bag to a plate and let rest, 3 minutes. Gently shake, then carefully open bag and scoop out potatoes.
Plate dish as pictured on front of card, placing patty on bottom bun and topping with BBQ sauce, blue cheese, crispy onions, and top bun. Bon appétit!