Preparation

Melt butter (1 Tbsp) in a skillet over medium-low heat. Add the thinly sliced yellow onion (1 small) with a pinch of salt and cook slowly, stirring occasionally, for 15–20 minutes until deeply caramelized and golden. Set the onions aside.

Season the ribeye or sirloin steak (6 oz) with salt, pepper, and garlic powder (½ tsp). In the same skillet, melt butter (1 Tbsp) over medium-high heat and sear the steak for 3–4 minutes per side until your desired doneness is achieved. Remove the steak from the skillet and allow it to rest while preparing the sauce.

Lower the heat to medium and pour in the beef bone broth (½ cup). Stir in the soy sauce or coconut aminos (1 Tbsp), Dijon mustard (1 tsp), apple cider vinegar (1 tsp), garlic powder (¼ tsp), onion powder (¼ tsp), cinnamon (a pinch), and a pinch of salt and pepper. Simmer the sauce gently for 3–4 minutes, letting it reduce slightly. Whisk in butter (½ Tbsp) to finish the sauce and keep it warm.

Return the steak to the skillet or place it on a serving plate. Top the steak with the caramelized onions (from earlier) and sprinkle the shredded Gruyère cheese (1 oz) over the top. Tent the steak loosely with foil for 1–2 minutes to allow the cheese to melt, or briefly place under a broiler if a bubbly, golden finish is desired.

Spoon the warm spiced au jus around the steak and garnish with fresh thyme leaves (1 tsp) if desired. Serve immediately.