1. Preheat the oven to 400 degrees.
2. Prep your ingredients: Peel, seed, and cube the butternut squash. Cut the stems off of the sprouts.
3. Place the squash on a parchment-lined cookie sheet and cover with foil. Put into the oven and cook until the squash is tender.
4. While the squash is cooking, finish prepping the sprouts. Using a food processor and the slicing attachment, chop all of the sprouts. (If you don't have a food processor you can use a mandolin or just slice them by hand.)
5. Next, season the steak with salt and pepper and cook to your preferred doneness on a grill or stovetop.
6. Once the squash is tender, remove from the oven and transfer to the bowl with the shredded sprouts. Stir together with the vinegar, walnut oil, and olive oil, and season with salt and pepper to taste.
7. Thinly slice the steak on a bias, against the grain, and shingle onto a platter. Serve with the warm roasted squash salad.