How to Make It
In a large sauce pan, sauté shallot in 2 tablespoons of oil over moderate heat until softened, about 3 minutes. Add the rice and cook, stirring, for 3 minutes. Add the stock, salt, and pepper and bring to a boil. Cover and simmer over low heat until the broth is absorbed and the rice is tender, about 45 minutes.
Remove from the heat and let stand, covered, for 10 minutes. Fluff with a fork and toss with 2 tablespoons of olive oil, vinegar, tomatoes, mozzarella, and basil. Serve warm or chilled.
If eating a gluten-free diet, be sure to use gluten-free stock.