Slice the onion and peppers into slices. Place into a large frying pan under medium-low heat with olive oil. Saute until the onions become translucent and the peppers become soft.
While the veggies are cooking, cut the chicken into strips. Set aside.
Once onions and peppers are soft, add in the chicken. Saute until chicken is almost cooked through. Then add in ¼ of a package of chili seasoning. Stir until everything in the pan is evenly covered. Then fry for another 5 mins.
Set aside.
In a separate frying pan over high heat, place a corn tortilla until its toasted, then flip to toast the other side.
Plate the tacos with the corn tortilla on the plate followed by a sprinkle of cheese, the chicken/onion/ pepper mixture, salsa and sour cream topped with cilantro.