Starting with the recipe for grilled turkey burgers taken from Cook's Illustrated, I have now mastered the art with the following recipe and cooking technique:
Ingredients:
1.25 lbs ground turkey (the 7% fat stuff, not the extra lean stuff)
2 tbsp Dijon mustard
2 tbsp Worcestershire sauce
0.5 tbsp freshly ground black pepper
0.5 tbsp ground sea salt
0.5 cups ricotta cheese (not the low fat stuff, the real thing)
I first start by combining all the non-turkey ingredients in a bowl until well mixed. I then add the ground turkey, and mix with a spoon until the non-turkey ingredients are evenly mixed into the turkey meat. The changes from Cook's Illustrated are basically a doubling of the flavoring ingredients (mustard, worcestershire, salt, pepper) for a more savory flavor.
Cooking technique for a gas grill:
The original Cook's Illustrated instructions called for grilling the burgers on high temp for 5 minutes, flipping them, then cooking for another 5 minutes on high heat. Next you were supposed to turn the heat down to medium-low and finish the burgers off at medium-low.
The problem I ran into: After five minutes of grilling at high heat, the turkey patties were still too soft/mushy. Each time I would try to flip them, they would disintegrate on the grill.
So instead, after preheating the grill on high for 15 minutes (followed by the usual scraping/brushing then coating with canola oil), I turn all burners down to medium-high. I cook the patties for 10 minutes without flipping them. After ten minutes, I flip them, and cook for another 5 minutes.
By extending the initial cooking to 10 minutes, the patties are nice and firm when you first flip them. As a result, you don't have problems with bits and pieces falling off as you flip them. The result is much better than the original recipe.