Step 1 Preheat oven to 180°C. Spray the inside of a round 20cm baking tin with olive oil and line the base with a sheet of baking paper.
Step 2 Heat olive oil in a large non-stick frying pan set over medium–high heat. Add onion and cook, stirring, for 3 minutes. Add sweet potato; cook, stirring, for 3 more minutes, or until vegetables are soft. Add crushed garlic; cook, stirring, for another 30 seconds.
Step 3 Whisk eggs with ricotta and parmesan in a large mixing bowl. Add sweet-potato mixture to bowl with grated zucchini and chopped semi-dried tomatoes and herbs. Season frittata mixture with black pepper and stir to combine.
Step 4 Pour frittata mixture into the prepared baking tin and bake for 35 minutes, or until set, puffed up and golden. Remove baking tin from oven and leave to cool for 10 minutes. Remove frittata from tin and slice into quarters.
Step 5 Serve frittata with steamed green beans and snow peas.
NOTE: Nutrition information, time to make and costings apply to main dinner recipe only.