Warm olive oil in a large skillet over medium heat. Add chopped onion and minced garlic, cooking for 2-3 minutes until the onion turns translucent.

Introduce the ground beef to the skillet, using a spatula to break it apart. Cook for approximately 5-7 minutes until it browns. Drain any excess fat if necessary.

Mix in the diced zucchinis, dried oregano, ground cumin, salt, and pepper. Continue cooking for another 5-7 minutes until the zucchinis are soft.

Stir in the drained diced tomatoes, and let the mixture simmer for 5 more minutes to blend the flavors.

Serve the beef and zucchini over a bed of cooked rice. Optional: Garnish with fresh parsley and crumbled feta cheese.