Nachos with Poblanos, Fresh Salsa, and Guacamole

To roast poblanos: Place a rack in the oven about 8 inches from heat source; preheat broiler. Arrange poblanos on a baking sheet and broil, turning occasionally, until just charred and softened, 8 to 10 minutes. Transfer to a heatproof bowl and cover with plastic wrap; set aside to steam for 10 minutes. Use a paring knife to scrape off as much skin as possible, then remove seeds. Chop poblanos in 1-inch pieces; set aside. To make salsa: Heat oil in a small pot over medium heat. Add chilies de arbol and cook, turning often, until just browned and toasted, about 2 minutes. Add tomatillos, tomatoes, and 1/2 cup water and bring to a boil. Reduce heat to medium-low, cover, and simmer 20 minutes. Uncover and boil gently until just thickened, about 10 minutes more. Transfer to a blender and carefully pulse to make a slightly chunky salsa. Transfer to a bowl, stir in salt and black pepper, and set aside to cool. To make guacamole: In a medium bowl, stir together onion, 1/4 cup cilantro, lime juice, avocados, jalapeño, salt, and pepper; set aside. To assemble: Preheat oven to 425 degrees. Spray a large baking sheet with cooking spray, then scatter half of the chips on the tray and top with half of each of the Monterey Jack cheese, beans, and roasted poblanos. Repeat process with remaining chips, cheese, beans, and peppers, then spoon about 3/4 cup salsa over the top and bake until cheese is bubbly and just browned on top, about 10 minutes. Remove from oven and place on plates. Spoon crema over nachos, then top with guacamole, Cotija cheese, and remaining 1/4 cup cilantro. Serve with remaining salsa on the side.