Step 1

Heat oil in a large pot over high heat. Add onion, salt, and ground beef. Cook and stir with a wooden spoon or spatula until meat is browned and crumbled into small pieces, about 5 minutes. Stir in flour and cook for 2 minutes. Add poblano pepper, garlic, chili powder, cumin, black pepper, cayenne, and oregano; cook, stirring, for 2 to 3 minutes.

Step 2

Stir in diced tomatoes and crushed tomatoes. Measure water using the empty tomato cans and pour into the pot. Bring to a simmer, stirring occasionally, then reduce heat to medium-low. Let simmer, stirring occasionally, for 30 minutes before stirring in kidney beans. Continue simmering until bubbling and fragrant, about 30 minutes more. Taste for seasoning and adjust.

Step 3

Preheat the oven to 400 degrees F (200 degrees C).

Step 4

Place a deep 9x13-inch baking dish on a baking sheet. Transfer chili to the dish, being sure to leave at least 1 inch of space at the top. Stir to evenly distribute.

Step 5

Whisk corn muffin mix, 1/2 of the Cheddar cheese, eggs, and milk together in a bowl until smooth. Spoon evenly over chili until the surface is covered. Sprinkle with remaining Cheddar cheese.

Step 6

Bake in the preheated oven until cornbread crust is browned and a toothpick inserted into the crust comes out clean, about 30 minutes.

Step 7

Spoon or ladle into a dish and garnish with sour cream and cilantro.