French Onion Steak Pinwheels: Pan-Seared

Ingredients

• 1 1/2 lbs flank steak or skirt steak
• 1 tsp salt
• 1 tsp black pepper
• 1 tsp garlic powder
• 2 large yellow onions, thinly sliced
• 3 tbsp unsalted butter
• 1 tbsp olive oil
• 2 tbsp dry white wine or balsamic vinegar
• 1 tsp fresh thyme leaves
• 6 oz Gruyère cheese, thinly sliced or shredded
• 2 tbsp neutral oil
• 2 tbsp cold butter