Combine the minced shallots, oil, vinegar, fresh squeezed orange juice, and lemon zest (if using) in a small jar with a screw-top lid. You could also use a salad shaker.
1 small shallot, ¾ cup extra-virgin olive oil, ¼ cup lemon-flavored white balsamic vinegar, 5 tablespoons freshly squeezed orange juice, ¼ teaspoon finely grated lemon zest