Step 1Preheat oven to 160°C. Lightly spray a 20cm round spring-form baking tin with olive oil.
Step 2Spray a large non-stick frying pan with oil and set over medium heat. Sauté onion for 5 minutes, or until softened. Add garlic, zest and zucchini; cook, stirring, for 2 minutes. Set aside to cool.
Step 3Whisk eggs and ricotta in a large bowl. Stir through the zucchini mixture, spinach and three-quarters of the basil.
Step 4Meanwhile, lightly spray 1 filo sheet with olive oil. Fold in half. Place over base and sides of prepared pan. Spray with oil. Repeat with the remaining filo, overlapping each sheet slightly, to completely line the pan.
Step 5Pour the egg mixture into filo base. Fold any excess filo over filling to cover edges slightly. Bake for 35–40 minutes, or until tart is set and golden. Meanwhile combine the tomatoes, onion, balsamic and extra basil. Serve tart topped with the tomato salad, and with baby rocket drizzled with olive oil.