Preheat: Preheat your oven to 400 degrees F (200 degrees C).
Season: Brush each side of the cauliflower steaks with olive oil and sprinkle with the paprika.
Bake: Place the cauliflower steaks on a baking sheet and bake for about 20 minutes, or until tender and slightly caramelized.
Blend: While the cauliflower is baking, blend the walnuts, garlic, lemon juice, 1 tablespoon of olive oil, and parsley in a blender until smooth to make the sauce.
Serve: Once the cauliflower is done, serve the steaks topped with the walnut sauce.