Heat olive oil in a large skillet over medium-high heat. Sear chicken breasts for 3-4 minutes on each side until golden brown.
Sprinkle taco seasoning over the chicken and add ½ cup water to create a flavorful sauce.
Bring to a simmer; reduce heat to low and cover. Cook for 20-25 minutes until chicken is tender.
Transfer chicken to a cutting board and shred with two forks. Return shredded chicken to skillet with remaining sauce; simmer for an additional 5-10 minutes.
Warm tortillas in a skillet or microwave.
Assemble tacos by filling warm tortillas with shredded chicken and your choice of toppings.