Mexican Zucchini and Corn Burrito

Name: Mexican Zucchini and Corn Burrito
Ingredients: 1 tablespoon vegetable oil; 1 medium onion, chopped; 2 medium zucchini, halved lengthwise and cut into 1/2-inch slices; 1 (10 ounce) package frozen whole kernel corn; 1 teaspoon dried oregano (dried); 1⁄2 teaspoon salt; 1⁄4 teaspoon pepper; 1 (14 ounce) can diced tomatoes with jalapenos (or Rotel, or tomatoes with chiles); 4 flour tortillas (we used jalapeno & cilantro flavored); 1⁄2 cup salsa (or to taste); 1 cup low-fat cheddar cheese or 1 cup cheddar cheese, shredded; 4 tablespoons low-fat yogurt (or to taste) or 4 tablespoons sour cream (or to taste); hot sauce (optional, to taste)