Preparation

• Line a medium- or fine-mesh strainer with cheesecloth, and set over a medium bowl.
• Purée 1/4 cup of the oil with the chives and a pinch of salt in a blender until mostly smooth, about 2 minutes. Transfer to the strainer and let drip, undisturbed, until the dripping stops, about 20 minutes. Gently squeeze the cheesecloth to release the remaining oil. Discard the cheesecloth.
• Meanwhile, in a 4-quart pot, heat the remaining 1 Tbs. oil over medium-high heat until shimmering. Add the onion and caraway seeds and cook, stirring occasionally, until browned and crisp in places, about 6 minutes. Add the rutabaga, tomatoes with their juices, 1cup of the broth, and the garlic, and bring to a boil. Reduce the heat to medium low, cover, and simmer until the rutabaga is very soft, about 1hour, adding a little water if the pot gets too dry. Add another 1 cup of broth. Transfer half of the mixture to the blender, and purée until very smooth. Press through a medium-mesh strainer set over a bowl. Repeat with the rest of the mixture.
• Wipe the pot clean, and return the purée to the pot. Add the remaining 1 cup of broth, the lemon juice, 3/4 tsp. salt, and 1/2 tsp. pepper, and bring to a boil over medium-high heat. Lower the heat to medium, add the cream, and cook until just heated through. Season to taste with salt and pepper.
• Ladle the soup into serving bowls, drizzle with the chive oil and a little hot sauce, if using, and sprinkle with the chopped nuts.