Before starting, preheat the oven to 450°F. Remove 2 tbsp (4 tbsp) butter from the fridge and set aside to come up to room temperature. Wash and dry all produce. Cut potatoes into 1/2-inch wedges. Add potatoes, half the Montreal Steak Spice and 1 tbsp (2 tbsp) oil to an unlined baking sheet. Season with salt, then toss to coat.Roast in the middle of the oven, flipping halfway through, until tender and golden-brown, 25-28 min.

Meanwhile, cut bacon crosswise into 1/4-inch strips. Heat a large non-stick pan over medium heat.When hot, add bacon. Cook, flipping occasionally, until crispy, 5-7 min.**Remove the pan from heat. Using a slotted spoon, transfer bacon to one side of a plate to cool slightly. Set aside.Reserve bacon fat in the pan.

Meanwhile, cut ciabatta into 1/2-inch pieces. When bacon is done, reheat the pan with bacon fat over medium. When hot, add ciabatta. Season with salt and pepper. Cook, stirring often, until golden-brown and crisp, 5-6 min. Remove from heat, then add croutons to the other side of the plate with bacon.

Pat steak dry with paper towels, then season with salt and remaining Montreal Steak Spice.Reheat the same pan over medium. When hot, add 1/2 tbsp (1 tbsp) oil, then steak. Sear until golden-brown, 1-2 min per side. Remove from heat, then transfer steak to another unlined baking sheet. Roast in the top of the oven until cooked to desired doneness, 5-8 min.** When steak is done, transfer to a cutting board. Cover loosely with foil and set aside to rest, 5 min.

Meanwhile, roughly chop parsley. Zest, then juice half the lemon. Cut remaining lemon into wedges. Peel, then mince or grate garlic. Add mayo, half the Parmesan, half the lemon zest, half the garlic and 1 tbsp (2 tbsp) lemon juice to a large bowl. Season with salt and pepper, then whisk to combine. Set aside.Add remaining lemon zest, remaining garlic, half the parsley and 2 tbsp (4 tbsp) softened butter to a small bowl. Season with salt and pepper, then stir to combine. (NOTE: This is your compound butter.)

Add spinach, bacon and croutons to the large bowl with dressing, then toss to combine. Thinly slice steak. Divide steak, potato wedges and salad between plates. Sprinkle remaining Parmesan over salad. Dollop compound butter over steak to melt. Sprinkle remaining parsley over potatoes. Squeeze a lemon wedge over salad, if desired.