Heat olive oil in a skillet over medium heat.
Add the chopped onions and sauté until translucent.
Stir in minced garlic and cook for an additional minute.
Add the diced tomatoes and cook until softened.
In a separate pot, boil the chicken breasts until fully cooked, about 20 minutes.
Remove the chicken, shred it with two forks, and set aside.
Add chipotle peppers, cumin, oregano, salt, and pepper to the skillet.
Incorporate shredded chicken into the skillet and mix well.
Simmer for 5-10 minutes, allowing flavors to meld.
Serve hot, garnished with fresh cilantro.