Trim stems off Brussels sprouts and halve vertically (quarter if larger than a ping-pong ball). Cut potatoes into ½" wedges. Halve and peel onion. Slice halves into thin strips. Stem and mince thyme. Pat steaks dry, and season both sides with a pinch of salt and pepper.

Place potatoes on one half of prepared baking sheet. Toss with 1 tsp. olive oil, ¼ tsp. salt, and a pinch of pepper. Spread into a single layer on their side. Place Brussels sprouts on empty half. Toss with 1 tsp. olive oil, garlic pepper, and a pinch of salt. Spread into a single layer on their side. Roast in hot oven until tender, 12-15 minutes. While vegetables roast, cook onion.

Place 2 tsp. olive oil in a medium non-stick pan over medium heat. Add onion, red wine, beef demi-glace, thyme, and ¼ cup water to hot pan. Stir occasionally until browned and liquid is mostly evaporated, 10-13 minutes. Remove from burner. Season with a pinch of salt and pepper. While onion cooks, cook steak.

Place another medium non-stick pan over medium heat and add 1 tsp. olive oil. Add steaks to hot pan and cook until browned and steaks reach a minimum internal temperature of 145 degrees, 5-7 minutes per side. Remove from burner. Transfer steaks to a plate and rest at least 3 minutes. Reserve pan; no need to wipe clean.

Return pan used to cook steaks to medium heat. Add cream base, cheese, and a pinch of pepper to hot pan. Stir occasionally until combined and smooth, 1-2 minutes. Remove from burner. Plate as pictured on front of card, topping steak with onion and sauce with potatoes. Bon appétit!