Preheat the oven to 425 degrees . Drizzle enough EVOO onto a large rimmed baking sheet to coat the bottom. Add the sausages, tomatoes, scallions and garlic, season with salt and pepper and pour the vinegar on top. Roast, turning the sausages and vegetables once halfway through cooking, 30 minutes.
Divide the sausages and vegetables among 4 plates and top with the cauliflower and basil.