Prepare Oven and Dish: Set your oven to preheat at 360°F (180°C). Lightly grease your chosen baking dish (8x8 inch or 9-inch deep pie plate) with cooking spray or butter.

Dry the Squash: Place the shredded zucchini/squash onto a clean kitchen towel or several layers of paper towels. Wrap tightly and squeeze firmly to remove as much excess liquid as possible. Set aside.

Sauté Aromatics: Melt the butter in a large skillet over medium heat. Add the chopped onion and sauté, stirring occasionally, until softened and lightly golden, roughly 5-7 minutes. Stir in the minced garlic and cook for about 30 seconds more until fragrant.

Cook Squash: Add the squeezed squash to the skillet along with a pinch of salt. Cook, stirring frequently, until the squash is tender and appears relatively dry, typically 4-5 minutes. Remove skillet from heat.

Combine Ingredients: In a large mixing bowl, combine the cooked squash and onion mixture with the corn, cottage cheese, crumbled feta, chopped red bell pepper, fresh dill, flour, baking powder, dried oregano, black pepper, and the remaining ⅛ teaspoon of salt. Stir everything together until well incorporated.

Incorporate Eggs: Lightly beat the 8 large eggs in a separate medium bowl. Pour the beaten eggs into the vegetable mixture and stir gently until just combined. Do not overmix.

Bake: Pour the egg and vegetable mixture evenly into the prepared baking dish. Bake in the preheated oven at 360°F (180°C) for 35 to 40 minutes. The casserole is done when the center is set (a knife inserted near the center comes out clean) and the edges are pulling away slightly and are lightly browned.

Rest Before Serving: Carefully remove the casserole from the oven and let it stand on a wire rack for at least 10 minutes before slicing and serving. This allows the casserole to firm up slightly for easier cutting.