Preheat the Oven: Begin by preheating your oven to 360°F (180°C).
Prep the Veggies: Peel the zucchini and carrots. Grate them using a box grater and set aside to drain excess moisture.
Mix the Wet Ingredients: In a large mixing bowl, crack the eggs and whisk them together with the sunflower oil until well combined.
Combine Dry Ingredients: In the same bowl, stir in the flour and baking powder until fully incorporated and creamy.
Incorporate the Filling: Add the grated zucchini, carrots, grated onion, cheese, salt, and pepper into the bowl. Mix until a homogeneous mixture forms.
Prepare the Pan: Grease a baking dish or pie pan with butter and flour, then line the bottom with parchment paper for easier removal.
Spread the Mixture: Pour the combined mixture into the prepared pan, spreading it evenly.
Bake: Place the pie in the oven and bake for 30-35 minutes or until the top is golden brown and the pie is set.
Cool and Serve: Remove from the oven, let it cool slightly, and slice it into wedges! Enjoy warm or at room temperature.