1. Cook the meatballs according to package directions. Preheat the oven to 350°F. Sprinkle the flour on a large piece of parchment paper and roll out the pizza dough into a 10-inch x 14-inch rectangle. Transfer the dough with the parchment to a baking sheet and spread the pizza sauce evenly over the dough.
2. Place the thawed spinach in a colander and press with the back of a spoon to remove as much moisture as possible. Divide the spinach evenly over the dough. Slice the meatballs and mozzarella cheese and arrange over the spinach. Sprinkle with oregano.
3. Take the long end of the dough and roll, using the parchment to help, and place seam side down on the baking sheet. Brush the top of the dough with olive oil. Cook the stromboli in the middle of the oven for 20 minutes. Remove the pan from the oven and pour out any excess moisture. Return pan to oven and bake until golden brown and crisp, 10 minutes. Serve on a cutting board and slice at the table.
Per serving: 746 calories, 37g fat, 12g saturated fat, 63mg cholesterol, 1137mg sodium, 84g carbohydrate, 7g fiber, 7g sugar, 28g protein