1 (.7 ounce) package dry Italian salad dressing mix (such as Good Seasons®)
1 pound boneless chicken pieces, cut into bite-size chunks
1 tablespoon butter
1 large onion, chopped
1 large green bell pepper, chopped
1 (10 ounce) package sliced crimini mushrooms
1 large tomato, chopped
2 cups shredded sharp Cheddar cheese
YIELD 6 servings
Whisk together the vinegar, olive oil, water, and Italian dressing mix in a bowl. Stir in the chicken; allow chicken to marinate while preparing the remaining ingredients.
Heat the butter in a skillet over medium-high heat. Stir in the onion and bell pepper; cook and stir until the onion has softened and turned translucent, about 5 minutes. Remove the the chicken from the marinade using a slotted spoon, and transfer to the skillet; reserve the remaining marinade. Cook and stir the chicken until no longer pink in the center, 3 to 5 minutes.
Stir in the mushrooms; cook and stir until they begin to soften, about 2 minutes. Add tomato and reserved marinade, then sprinkle cheese on top. Do not stir. Cover and simmer on low heat until cheese is melted and chicken is tender, about 20 minutes. Allow the dish to rest for a few minutes before serving.