Start by heating your avocado oil in a sturdy skillet over medium heat. Add the diced onion and cook, stirring occasionally, until it becomes soft and clear, which takes about 8 minutes.
Next, stir in the minced garlic, diced chipotle peppers, dried oregano, ground cumin, crushed fire-roasted tomatoes, and kosher salt. Bring this mixture to a gentle simmer and let it cook for about 7 minutes, allowing the flavors to meld beautifully.
Stir in your shredded cooked chicken breast and continue to cook for another 5 minutes, ensuring everything is well combined and heated through. Give it a quick taste and adjust any seasonings if needed.
To enjoy your delicious tacos, simply spoon the chicken tinga mixture onto low-carb tortillas. Garnish with fresh avocado slices, chopped cilantro, diced red onion, and crumbled cotija cheese. A squeeze of fresh lime juice adds a perfect tangy finish!