Prepare Steaks: In a bowl, mix steaks with salt, pepper, and lemon juice. Massage the steaks with the mixture.
Sauté Steaks: Add olive oil to a hot pan. Transfer the steaks to the pan and sauté on both sides until they change color.
Prepare Potatoes: Place Naxos potatoes in a baking pan. Add sliced onion, garlic rings, salt, pepper, dried oregano, and lemon juice. Mix well.
Add Water: Add water to the potato mixture in the baking pan.
Combine Steaks and Potatoes: Transfer the browned steaks to the baking pan with the potatoes.
Add Butter: Pour melted butter over the steaks and potatoes in the baking pan.
Bake: Bake in a preheated oven at 220°C (or 230°C for a higher temperature) for about 30 minutes.
Serve: Remove from the oven, place on a plate, and serve with freshly ground pepper and oregano leaves.