Preheat oven to 425°F (220°C). Toss cubed potatoes with olive oil, garlic powder, onion powder, salt, and pepper. Roast for 20–25 minutes until crispy.

While potatoes cook, sauté bell pepper and onion in a pan until soft and lightly charred. Set aside.

Season steak with salt, pepper, and any remaining seasoning. Sear in a hot pan until desired doneness, then let rest and slice thinly.

To make the sauce, whisk together Greek yogurt, olive oil, lemon juice, parsley, garlic powder, onion powder, Dijon mustard, salt, and pepper. Add water to thin as needed.

Assemble bowls with a base of roasted potatoes, then layer on steak, peppers, and onions.

Drizzle generously with garlic herb yogurt sauce and top with optional cheddar cheese. Serve warm.