Season the chicken with the seasoning mix and set aside.
Heat the oil in a large pot over medium heat.
Add onions, bell pepper and sauté until softened, about 8 minutes. Add garlic, sauté 1 minute longer. Add in flour, sauté 1 minute more.
While whisking pour in milk and chicken broth. Stir in tomatoes, corn, jalapeños, cumin, chili powder and season with salt and pepper.
Bring mixture to a light boil stirring frequently. Reduce heat to low and simmer for 20-25 minutes.
While the soup simmers, preheat the grill (or griddle pan) on medium high heat.
Place the chicken thighs on the grill (pan) and cook for 4 minutes. Flip and cook for 4 minutes more. Remove the chicken to a plate cover tightly with foil and let rest for 10 minutes.
Next, cut chicken into bite sized cubes.
Once the soup has simmered, stir in black beans and warm through. Stir in chicken and resting juices and cook for 1-2 minutes. Remove from heat, then stir in the cheese and cilantro.
Serve warm with avocado, more cheese, cilantro, jalapeño slices, lime wedges, hot sauce and tortilla chips.