Begin by cutting the ribeye steak into 16 equal pieces for even cooking. Scrub the Yukon Gold potatoes and bring salted water to a boil. Par-boil the potatoes for about 5-7 minutes until just tender, then drain and cool.

In a mixing bowl, combine soy sauce, ketchup, vegetable oil, white vinegar, brown sugar, and garlic powder. Whisk together to create a flavorful marinade.

Place cubed ribeye steak and baby Bella mushrooms into a resealable plastic bag. Pour marinade over them, ensuring they're well-coated. Massage the bag gently and refrigerate for at least 1 hour.

Soak wooden skewers in water for at least 30 minutes to prevent burning on the grill.

Thread the marinated steak pieces, Yukon Gold potatoes, and mushrooms onto soaked skewers, leaving small gaps for even cooking.

Preheat your grill to medium-high heat, around 400°F (200°C). Lightly oil the grill grate.

Place skewers on the grill and cook for about 12-15 minutes, turning every 3-4 minutes for even cooking.

Baste kabobs with reserved marinade during grilling for enhanced flavor and moisture.

Remove kabobs from grill, serve warm, and optionally garnish with cilantro or chives.