Preheat your oven to 375F and position your oven rack in the middle of the oven (if it’s too high your tacos could get too toasty).
Fill the tacos:
On an oven safe 9x13 baking dish, line up 12 taco shells, vertically, so they're easier to fill. Fill with cooked chicken and top with cheese.
In a medium bowl, combine the shredded chicken, the ⅓ cup salsa or salsa verde, and half of the shredded cheese. If the chicken is very cold, warm it up for a minute in the microwave.
Fill the taco shells with the chicken mixture and sprinkle the remaining cheese over the top.
Bake:
Bake the filled tacos for 10 to 12 minutes until the taco shells are crispy and the cheese is melted.
Add toppings:
Once the tacos are ready, load them up with toppings and serve immediately.