Measure 1 cup barbecue sauce; set aside. With small, sharp knife, make 4 shallow slashes in each side of fish from head to tail. Stuff cavities with reserved solids from sauce. Rub about 1 tablespoon cooled sauce over each side of fish. Lay 3 stalks lemongrass across bottom of a casserole or baking dish just large enough to hold both fish without stacking. Scatter half of ginger, limes, onion slices and lemon verbena over bottom of baking dish. (This will provide a flavor base for fish to rest on while marinating.) Lay fish in the baking dish and pour half of remaining sauce on top. Arrange remaining 3 lemongrass stalks, ginger, lime, onion, and lemon verbena on top. Cover tightly and refrigerate fish and reserved sauce 8 hours or overnight.
Prepare a fire in a charcoal grill, or preheat a gas grill to medium hot. Remove layer of lemongrass and lay it on grill, avoiding hottest sections. Lay fish side by side on top of lemongrass (to provide flavor and prevent sticking). Grill fish 6 to 8 minutes. Baste each snapper with about 2 tablespoons of remaining sauce. Arrange lemongrass from bottom of dish next to fish on grill. Using a large spatula, roll fish onto lemongrass, exposing uncooked side to heat of grill. (Rolling method keeps tender fish from falling apart.) Sprinkle with thinly sliced lemongrass. Cook fish 4 to 6 minutes longer, basting with remaining sauce. Using a spatula, roll fish onto a baking sheet.
(To broil fish: Preheat broiler and broiler pan. Lightly spray pan with nonstick spray. Remove one fish from marinade; place on pan and generously baste with reserved sauce. Broil 5 inches from heat source 5 minutes; baste with sauce and broil 5 minutes more. Turn fish over; generously baste with sauce and broil 5 minutes. Baste with sauce and broil 3 to 5 minutes more or until fish flakes easily when tested with a small, sharp knife. Repeat with remaining fish.)
Recommended ingredient: Fresh lemongrass is available at Asian and specialty markets. Dried lemongrass can be substituted and is available at most supermarkets or online at importfood.com. Lemon verbena is available at specialty markets.
For more from Michel Nischan, visit his website: www.michelnischan.com