Place the ground turkey in a mixing bowl, then add the grated red onion, shredded cheddar, ground cumin, ground coriander, chili powder, taco or chili sauce, salt and some pepper. Mix to combine. Using the side of your hand, score the meat with an X, dividing it into four equal portions. Form each portion into 1-inch thick patties. Wash your hands after handling the raw poultry.
Place a large skillet over medium-high heat with two turns of the pan of EVOO, about 2 tablespoons. Once the skillet is hot, add the taco burgers and cook on each side for 6-7 minutes, or until cooked through.
While the burgers are working, put together the guacamole and fresh tomato salsa. For the guacamole, place the flesh of the avocados in the bottom of a mixing bowl. Add half of the minced garlic, the juice of one of the limes and half of the minced jalapeño. Mash together, taste and add more salt and pepper, to taste.
For the fresh tomato salsa, in another bowl, combine the chopped tomatoes, the remaining half of the minced jalapeño, the minced red onion, the remaining lime juice and the cilantro. Season with salt and pepper and stir to combine.
Toast the rolls until golden brown. Remove the burgers from the skillet to the bottom of the toasted rolls, then top with a spoonful of guacamole and a spoonful of fresh tomato salsa, a dollop of sour cream and some of the shredded lettuce. Arrange the tops of the toasted rolls. Serve the burgers alongside some tortilla chips and the remaining guacamole and fresh tomato salsa.