Heat oil in a large saucepan over medium-high heat. Add chicken and cook, stirring occasionally, until browned, 3 to 4 minutes. Transfer to a plate.
Add zucchini, shallot, Italian seasoning and salt and cook, stirring often, until the vegetables are slightly softened, 2 to 3 minutes. Add tomatoes, broth, wine and orzo (or other tiny pasta); increase heat to high and bring to a boil, stirring occasionally. Reduce heat to a simmer and cook until the pasta is tender, about 8 minutes, or according to package directions. Stir in spinach, the cooked chicken and any accumulated juices from the chicken; cook, stirring, until the chicken is heated through, about 2 minutes.
