Place the chicken breasts into a saucepan and fully submerge them in water. Bring the water to a boil over medium-high heat, then lower the heat and let it simmer gently for 10–12 minutes, or until the chicken reaches an internal temperature of 165°F (74°C).

Remove the chicken from the pot and transfer it to a cutting board or bowl. Using two forks, shred the meat into fine strands.

Warm the vegetable oil in a skillet over medium heat. Add the minced onion and sauté for about 3 minutes, or until softened and translucent.

Stir in the garlic and cook for another 30 seconds until fragrant. Add the cumin, oregano, chili powder, and salt, stirring continuously for 1 minute to bloom the spices.

Incorporate the salsa into the skillet. If the mixture appears too thick, add a small amount of water to loosen it. Let it heat through briefly.

Add the shredded chicken to the skillet, mixing it thoroughly with the seasoned salsa. Allow the mixture to simmer together for 2–3 minutes to meld the flavors.

Serve immediately in warmed tortillas or taco shells. Add your preferred toppings such as shredded lettuce, diced tomatoes, avocado, cheese, or sour cream.