Heat oil in a skillet over medium. Add beef and onion; cook, crumbling, until browned. Stir in garlic for 30 seconds, then drain.
Transfer the beef mixture to the slow cooker. Stir in broth, tomatoes with chiles, black beans, corn, taco seasoning, cumin, and pepper.
Cover and cook on Low for 3 hours, until hot and fragrant.
Stir in cream cheese, processed cheese, cheddar, and evaporated milk. Cover and cook 30 minutes more, then whisk until smooth.
Season with salt and lime juice. If you prefer a looser soup, splash in a bit more broth or milk.
Ladle into bowls and finish with crushed tortilla chips or your favorite nacho toppings.
Notes
Variation: Swap the beef for ground turkey or omit the meat and add an extra can of beans for a hearty vegetarian version. For a touch of heat, add a minced jalapeño with the tomatoes.Storage: Cool and refrigerate in an airtight container up to 4 days. Rewarm gently over low heat, stirring in a splash of milk to loosen if needed. This soup also freezes well for 2 months.This recipe is an original creation inspired by classic Crockpot Nacho Cheese Soup Recipe flavors. All ingredient ratios and instructions are independently developed.