To Make The Guacamole, Place The Avocado, Cilantro, Sour Cream, Chili Powder, Salt, And Pepper In A Food Processor And Pulse Until Smooth.. Mix Chicken, Canned Chiles, Jalapeno Pepper, Green Onions, Oregano, Salt, Garlic Powder, And Pepper In A Bowl. Form The Mixture Into 4 Patties. Preheat An Outdoor Grill For Medium Heat. Lightly Oil The Grill Grate. Grill Each Patty 5 Minutes Per Side, Until Well Done. Move The Patties To A Cooler Area Of The Grill To Keep Warm, And Top Each Patty With A Slice Of Cheddar Cheese. Lightly Grill The Buns While The Cheese Is Melting. Spread The Bottom Of Each Bun With Guacamole, And Top With 1/4 Cup Of Shredded Lettuce And A Grilled Chicken Burger. Spoon 1 Tablespoon Of Salsa On Each Burger And Top With The Other Half Of The Bun To Serve.