Place the chicken breasts in a medium saucepan and cover with water. Bring to a boil over medium-high heat, then reduce heat to medium-low and simmer for 15 minutes or until the chicken is cooked through.
Remove the chicken from the water and let cool slightly. Shred the chicken using two forks and set aside.
Heat the olive oil in a large skillet over medium heat. Add the sliced onion and cook for 5 minutes until softened.
Add the minced garlic and cook for 1 minute until fragrant.
Stir in the diced tomatoes, chopped chipotle peppers, adobo sauce, oregano, cumin, smoked paprika, salt, and black pepper. Cook for 5 minutes, stirring occasionally.
Add the shredded chicken, chicken broth, and apple cider vinegar to the skillet. Stir to combine.
Reduce the heat to low and simmer for 10 minutes, allowing the flavors to meld and the sauce to thicken slightly.
Taste and adjust seasoning if needed. Serve hot as a filling for tacos, tostadas, or burritos.