Sauteed onions and chicken breasts are doused in buffalo sauce and smothered with melted cheese in this 15 minute meal that's perfect for lunch or dinner.
Heat a large heavy skillet over medium-high heat. Pour in olive oil. Add in onions and saute until onions are soft and translucent, 5 to 7 minutes.
Meanwhile, place chicken breasts between two sheets of parchment or wax paper. Use a meat tenderizer or rolling pin to pound out the chicken until 1/4-inch thick.
Remove sauteed onions from skillet and set aside in a bowl. Place chicken breasts directly into hot pan. Cook about 2 minutes, then flip and cook another 2 minutes.
Use two spatulas to chop the chicken into bite-size pieces. If you are using a non-stick skillet, remove the chicken and cut on a cutting board and then return to skillet.
Add onions back to pan with chicken and pour buffalo sauce over the whole thing. Use 1/4 to 1/2 cup depending on personal tastes for spiciness. Stir to combine. Continue cooking until all chicken is cooked through.
Add slices of cheese over the top. Cover the pan until cheese is completely melted.
Serve on toasted hoagie buns with tomato slices, lettuce, and a drizzle of bleu cheese dressing.