Heat 1 tablespoon olive oil in a Dutch oven or stockpot over medium-high heat. Add diced onions and minced garlic, sautéing until tender and fragrant, about 3-4 minutes.

Stir in chili powder, cumin, salt, and pepper. Toast the spices for 2-3 minutes, stirring frequently to release their aromatic oils and prevent burning.

When browned bits develop on the bottom of the pot, use a splash of chicken broth to deglaze, scraping up all the flavorful bits.

Add fire-roasted tomatoes with juice, drained black beans, corn, and remaining chicken broth. Stir to combine everything evenly.

Increase heat and bring the soup just to a boil, then reduce heat to maintain a gentle simmer for 10-15 minutes, allowing flavors to meld together.

Stir in shredded chicken and continue heating until warmed through, about 2-3 minutes.

For homemade tortilla strips: Preheat oven to 400°F. Slice corn tortillas into thin strips and toss with 1 teaspoon olive oil and a pinch of salt.

Spread tortilla strips on a baking sheet and bake for 8-12 minutes until golden and crispy. Cool before serving.

Serve soup warm topped with crispy tortilla strips, fresh cilantro, lime wedges, sliced jalapeños, and Cotija cheese.