Step 1Heat a saute pan over medium heat until hot. Add the olive oil, then stir in the green onions and garlic. Add a pinch each of salt and pepper and cook, stirring frequently, until the onions are softened, about 4 to 5 minutes. Remove from heat and set aside.
Step 2In a large bowl, crumble the turkey and add one-fourth teaspoon salt and one-eighth teaspoon pepper.
Step 3In a separate bowl, beat the eggs with the cumin, Worcestershire sauce and barbecue sauce. Stir in the mixture with the turkey, then fold in the onions and garlic, along with any liquid remaining in the saute pan. (This will help to keep the burgers from getting dry.)
Step 4Fold in the panko crumbs gently, until all of the ingredients are thoroughly mixed. Separate the mixture into 6 portions, and form burger patties fitted to the shape of the bun. Cover and refrigerate them (up to 4 hours) while assembling the other components to give the flavors time to marry.
Step 1On a grill or stove burner heated over high heat, or under the broiler, grill or broil the peppers until the skins are charred and blackened on all sides. Immediately move them to a glass bowl and cover tightly with plastic wrap. Set aside to give the chiles time to cool. Peel the skins (they should peel or brush off easily), then core and seed the peppers. Cut each chile into 3 pieces.
Step 1Peel and lightly mash the avocados (the mash should be chunky) in a medium bowl. Fold in the onions, garlic, cilantro, salt, pepper, cayenne pepper, cumin and Tabasco sauce. Add the lime juice and stir to thoroughly combine. This makes a scant 3 cups guacamole. Cover and set aside.
Step 1Heat a grill or grill pan over high heat until hot. (The turkey patties may not be as firm as other burger meats; if using a grill, you might cook on a cast iron skillet over the grate if the patties feel a little soft.) Lightly oil the grill, and add the patties.
Step 2Reduce the heat to medium-high and grill until the undersides of the burgers are crisp and firm, 4 to 5 minutes and the lower half feels set (do not attempt to flip the burgers until they are set). Carefully flip the burgers with a spatula, then cook an additional 4 to 5 minutes and check the burgers for doneness.
Step 3Reduce the heat to medium-low and top each of the burgers with cheese. Continue to grill until the cheese melts. As the cheese is melting, brush the cut side of each bun half with a little oil or mayonnaise and add the buns to the grill to lightly toast. Remove the burgers and buns from heat.
Step 4Assemble the burgers: Divide the guacamole between the burgers, placing a scoop on the bottom bun of each burger. Top each scoop with a tomato slice. Place a burger on top of each tomato, then top each burger with a chile slice. Spread a tablespoon of mustard on the top half of each bun, then place the bun tops on the burgers. Serve the burgers with pickle spears.