Heat olive oil in a skillet over medium heat. Add diced onion and garlic, sauté until softened, about 3 minutes.
Add ground chicken to the skillet. Cook, breaking it apart with a spatula, until no pink remains, about 7 minutes.
Stir in taco seasoning and water. Reduce heat and simmer until most of the liquid has evaporated, about 5 minutes.
Warm corn tortillas according to package instructions.
Assemble tacos by placing chicken on tortillas, topping with shredded lettuce, diced tomatoes, shredded cheddar cheese, and fresh cilantro. Serve with Lime wedges.
