Heat a large, heavy-bottomed pot over medium-high heat and add about 1 tablespoon of olive oil. Add the chopped yellow onion and diced jalapeno pepper. Saute until the onion begins to soften, about 3-4 minutes. Then stir in the minced garlic, dried oregano, and chili powder. Cook for about 1 minute until fragrant. Pour in the chicken bone broth and add the chicken breast portions. Season with salt and pepper to taste. Bring everything to a boil, then reduce heat to a gentle simmer, cover, and cook for 10-15 minutes until the chicken is fully cooked through.
While the soup simmers, combine the cornstarch and water in a small bowl. Stir well until all the cornstarch is dissolved and the mixture is smooth. This slurry will help thicken the soup later.
Once the chicken is cooked through (after 10-15 minutes of simmering), remove the chicken from the pot and transfer it to a plate. Use two forks to shred the chicken into bite-sized pieces. Return the shredded chicken to the pot. Stir in the sour cream, shredded Monterey Jack cheese, chopped cilantro, frozen white sweet corn, and the juice of 1 lime. Mix thoroughly to combine all the flavors and melt the cheese. Next, re-stir your cornstarch slurry and pour it into the soup, stirring well. Allow the soup to simmer uncovered for about 10 minutes, stirring occasionally, until thickened. I find that letting the soup thicken gently really brings out the creamy texture!
Ladle the thickened, creamy soup into bowls. Top each serving with cooked bacon crumbles, cotija cheese crumbles, tortilla strips, and sliced avocado for extra flavor and texture. For a more authentic touch, I love to add plenty of fresh cilantro on top right before serving.