Preheat oven to 180C. Heat olive oil in an oven proof pan over medium heat. Add onion and cook until golden and translucent. Add sliced zucchini and sauté gently for approximately 5 minutes.
Whisk eggs in a large bowl. Stir in the cottage cheese and corn kernels. Season with salt and pepper. Pour egg mixture into pan over the sautéed zucchini. Sprinkle the fresh thyme on top and cook for 5 minutes on medium heat until eggs are just set.
Transfer the pan to the pre heated oven and bake for 15 minutes or until the top is golden and the mixture is cooked through.
Cut frittata into wedges and serve warm with a crisp green side salad.