Pepperoni Pizza Queso

Name: Pepperoni Pizza Queso
Ingredients: 2 tablespoons vegetable oil; 1 small yellow onion, diced; 1 red bell pepper, diced; 1 yellow bell pepper, diced; 1 green bell pepper, diced; One 10-ounce can diced tomatoes with green chiles; One 4.5-ounce can chopped green chiles; 8 ounces processed cheese, cubed; 4 ounces Cheddar cheese, shredded; 4 ounces mozzarella, shredded; 4 ounces fontina, shredded; 2 ounces Parmesan cheese, grated; Whole milk, as needed; 1 teaspoon fresh oregano, torn `; 1 small jalapeno pepper, diced; 1 cup sliced pepperoni, chopped; 2 Roma tomatoes, small dice; 2 tablespoons fresh basil leaves, torn; Pizza-flavored chips, for serving