Grate the zucchini and carrot. Finely chop the onion and dice the pepper. Slice the mushrooms and mince the garlic.
Sauté the Vegetables:
Heat a little vegetable oil in a large skillet over medium heat. Add the chopped onion and sauté until softened, about 3 minutes.
Add the grated carrot, diced pepper, and minced garlic. Cook for another 3-4 minutes until the vegetables begin to soften.
Add the sliced mushrooms and grated zucchini. Continue cooking, stirring occasionally, until the vegetables are tender and any excess liquid has evaporated, about 5 minutes. Season with salt and pepper to taste.
Prepare the Frittata Mixture:
Mix the Wet Ingredients:
In a large bowl, beat the eggs and then whisk in the milk until well combined.
Combine the Dry Ingredients:
In a separate bowl, mix the flour and baking powder (if using). Gradually whisk the dry ingredients into the wet mixture until smooth.
Combine Everything:
Stir the cooked vegetables into the egg mixture until well combined.
Cook the Frittata:
Cook the Frittata:
Preheat the oven to 180°C (350°F).
Lightly grease a baking dish or an oven-safe skillet with vegetable oil. Pour the frittata mixture into the dish.
Sprinkle the shredded mozzarella evenly over the top.
Bake:
Bake in the preheated oven for 20-25 minutes, or until the frittata is set and the top is golden brown.
Prepare the Sauce:
Make the Creamy Garlic Sauce:
In a small bowl, combine 3 tbsp sour cream, 2 tbsp mayonnaise, minced garlic, and chopped parsley. Mix well until smooth.
Serve:
Serve:
Once the frittata is baked, let it cool slightly before slicing. Serve warm, topped with the creamy garlic sauce.