Preheat your oven to 180°C (350°F).

Cook the kritharaki according to the package instructions until al dente, around 8–10 minutes. Drain and set aside.

In a skillet over medium heat, add olive oil and sauté the diced onion until translucent, about 5 minutes.

Add minced garlic and ground beef. Cook until browned, about 7–10 minutes. Season with oregano, salt, and pepper.

Stir in the tomatoes and simmer gently for 10–15 minutes to meld flavors.

Combine the cooked kritharaki with the meat sauce, mixing thoroughly.

Transfer to a greased baking dish and top with crumbled feta cheese.

Bake for 25–30 minutes until the top is golden and bubbly.

Let the casserole cool for a few minutes before serving.