Step 1In a large, non-stick skillet, saute the pears in the vegetable oil over high heat for 3 minutes, to give the slices a little color. Add the truffle oil and salt and simmer the slices until softened, about 10 minutes, carefully stirring so as not to break the slices. Stir in the sugar and continue to cook until the slices are caramelized, 2 to 4 minutes. Remove from heat and reserve both the pears and pear juice separately, holding each in a warm place.
Step 1In a large saute pan heated over medium-high heat, melt the butter and stir in the mushrooms. Stir in the garlic, along with one-half teaspoon salt and several grinds of pepper. Cook, stirring frequently, until the mushrooms are soft and lightly-browned. Remove from heat and strain the mushrooms, separately reserving both the mushrooms and any leftover liquid and holding in a warm place.
Step 1In a large skillet, crisp the bacon strips. Set the strips aside in a warm place, reserving 2 tablespoons bacon fat.
Step 2In a saute pan, heat the flour over medium heat. Whisk in the mushroom liquid, then the bacon grease, then the pear juice. Continue mixing to form a lumpy roux (add more flour if needed to form a lumpy roux). Whisk in the apple juice and bring to a simmer, whisking until the mixture has the consistency of ketchup (whisk in additional flour and/or apple juice to form the right consistency. Remove from heat. This makes about 2 cups gravy; set aside in a warm place.
Step 11. Peel and slice the onions into rings 1-inch thick.
Step 22. Fill a large mixing bowl with ice, and set a medium mixing bowl inside, surrounded by ice.
Step 33. Into the medium bowl, whisk together the flour, baking powder, salt and pepper. Form an indentation in the center of the flour mixture.
Step 44. In a measuring cup, combine the water and beer. Slowly pour the water/beer mixture into the flour, mixing until the batter has the consistency of lumpy pancake batter.
Step 55. In a large saucepan, heat the oil to 350 degrees. Dip the onion slices into the batter, then fry until golden-brown, 2 to 3 minutes. Drain on a rack and hold in a warm place.
Step 11. In a large bowl, combine the beef and chorizo along with the chopped onions. Season with the Worcestershire sauce, liquid smoke, Montreal steak seasoning and salt, kneading until the seasonings and flavorings are evenly disbursed. Divide into 8 burgers, shaping the patties so they are slightly larger than the diameter of the buns (they will shrink while cooking).
Step 22. Grill the patties to desired doneness. Hold in a warm place.
Step 1To assemble each burger, spoon about 2 tablespoons gravy on the bottom of each bun. Top with a layer of caramelized pears, and divide the bacon strips evenly between each. Place a burger patty over the bacon on each bun, then top each patty with an onion ring and a dollop (1 ounce) of goat cheese. Top the onion rings with mushrooms and spoon over more gravy. Complete the burger by adding the top bun.