In A Small Bowl, Combine Mayonnaise And 1 Tablespoon Basil. Cover And Refrigerate Until Serving. Coat Grill Rack With Nonstick Cooking Spray Before Starting The Grill. In A Bowl, Combine The Milk, Onion, Bread Crumbs, Salt, Pepper And Remaining Basil. Crumble Turkey Over Mixture And Mix Well. Shape Into Four Patties. Grill, Covered, Over Indirect Medium Heat For 5-6 Minutes On Each Side Or Until Meat Is No Longer Pink And A Thermometer Reads 165 Degrees F. Serve On Buns With Lettuce, Tomato And Basil Mayonnaise.