Heat 1 Tbsp olive oil in a large pot over medium heat, then add 1 medium yellow onion (diced), and 4 cloves garlic (minced). Cook until onion is soft, about 3 minutes.
Stir in ⅓ cup flour, 2 tsp cumin, 1 tsp each smoked paprika, oregano, salt, and ½ tsp ground black pepper.
Stir in 4 cups vegetable broth, 2 15-oz cans navy beans (drained), 2 15-oz cans chickpeas (drained), 1 15-oz can corn (drained), and 2 4-oz cans diced green chiles (not drained). Cover and let simmer for at least 5 minutes, up to 30 minutes.
Remove from heat. Optionally blend a little bit of the chili to create a thicker texture (either right in the pot with a handheld immersion blender, or by ladling about 2 cups into a countertop blender). Stir in 2 cups whole milk then serve with toppings like crushed tortilla chips, shredded Monterrey jack cheese, diced avocado, and cilantro!
