Tip: This recipe calls for chipotle chiles en adobo. They are typically found in Hispanic markets and well-stocked supermarkets. They provide an intense spiciness and a lovely smoky flavor. Serve with margaritas or your favorite Mexican beer, such as Pacifico or Tecate.
Preheat an electric skillet to 350 F according to manufacturer's instructions. Add the oil and let warm. Add the onions and cook, stirring occasionally, until softened and light golden brown, about 4 to 5 minutes. Add the garlic and cook until fragrant, about 1 minute.
Add the beef to the skillet and sprinkle generously with salt. Using a wooden spoon, break up the meat into walnut sized chunks and cook until browned on all sides, about 10 minutes (meat will not be cooked all the way through). Add the chipotle purée, chili powder and cumin and stir to combine. Add the tomato sauce and broth. Bring the mixture to a boil, cover, and reduce the heat to 250 F. Let the mixture simmer for 10 minutes.
Add the drained black beans and stir to combine. Season to taste with salt.
To serve, place a handful of tortilla chips on a plate and top with some of the beef. Layer with the toppings of your choice. Suggestions include sour cream, shredded cheese (such as cheddar or Monterey jack), sliced green onions, avocado or guacamole, salsa, hot sauce and shredded lettuce. Garnish with cilantro. Serve immediately.