Creating Scalloped Zucchini is simple if you follow these steps:

1. Preheat Oven: Preheat your oven to 375°F (190°C).
2. Prepare Zucchini: Slice the zucchinis into thin rounds. You can use a mandoline for uniform slices.
3. Season Zucchini: Place the zucchini slices in a large bowl. Drizzle with olive oil and sprinkle salt, pepper, garlic powder, onion powder, and thyme. Toss well to coat.
4. Layer Ingredients: In a greased baking dish, arrange half of the seasoned zucchini slices in an even layer.
5. Add Cheese: Sprinkle half of the cheddar and mozzarella cheeses over the zucchini layer.
6. Add Cream: Pour half of the heavy cream evenly over the cheese.
7. Repeat Layers: Add another layer of the remaining zucchini slices, followed by the rest of the cheese and cream.
8. Top with Parmesan: Finally, sprinkle the grated Parmesan cheese on top for a nice crust.
9. Bake: Cover the dish with aluminum foil and bake for 20 minutes. Then, remove foil and bake for an additional 10-15 minutes, or until the cheese is bubbly and golden brown.
10. Cool and Serve: Once out of the oven, allow it to cool for a few minutes. Garnish with fresh parsley before serving.

This step-by-step guide will help you create a mouthwatering Scalloped Zucchini without hassle.