Easy Moo Shu Pork with Tortillas

Name: Easy Moo Shu Pork with Tortillas
Ingredients: 1 teaspoon plus 1 tablespoon vegetable oil, such as safflower; 4 large eggs, lightly beaten; 1 pork tenderloin (about 1 pound), halved lengthwise and thinly sliced crosswise; 2 tablespoons cornstarch; Coarse salt and ground pepper; 1 pound shiitake mushrooms (stems removed), caps thinly sliced; 2 tablespoons minced peeled fresh ginger; 1/2 head napa cabbage, shredded; 5 scallions, thinly sliced; 1/3 cup soy sauce; 1/4 cup rice vinegar; Flour tortillas and hoisin sauce, for serving