Heat olive oil in a large skillet over medium heat. Add onions and salt and saute for 5 minutes. Add bell pepper and cook for 5 more minutes. Add garlic and stir for 1 minute. Add corn, beans, and chicken and stir to combine. Move the chicken mixture to a bowl and season with pepper, then stir in cheese and dry ranch dressing.
Begin heating about 1/2 inch of canola or vegetable oil in a large skillet over medium heat. Meanwhile, scoop 1 teaspoon of chicken mixture into the center of each wonton wrapper. Rub some water on two sides of the wrapper, then fold over to firmly seal, forming a triangle, and gently press out any extra air pockets. When the oil is hot, place 6 wontons at a time into oil. Cook about 1 minute per side until golden and crispy.