Super creamy, great color, and a nice Yom Tov alternative to butternut squash soup.
3 pounds red bell peppers, cut into 1-inch-wide strips
2 pounds ripe plum tomatoes, seeded and cut into 1-inch pieces
3 medium carrots, cut into 1-inch pieces
1 large yellow onion, cut into 8 wedges
1 large red onion, cut into 8 wedges
6 large fresh basil leaves, torn
4 sprigs fresh thyme
1 teaspoon sweet paprika
1/4 teaspoons cayenne, or more, optional
Kosher salt and freshly ground black pepper
9 tablespoons olive oil
3 – 4 cups vegetable or chicken broth
1/4 cup pareve milk, pareve whipping cream or soymilk
1-1/2 tablespoons red wine vinegar
Position a rack in the center of the oven and heat the oven to 450°F.
In a large roasting pan, toss the peppers, tomatoes, carrots, onions, basil, and thyme with the paprika, cayenne, 1 tsp. of salt, a few grinds of pepper, and 6 Tbs. of the oil. Roast the vegetables, turning them every 15 minutes or so, until tender and browned in spots, about 45 minutes.
Put one-third of the vegetables in a blender with 1 cup of the broth. Purée until very smooth, about 2 minutes. Strain through a fine- or medium-mesh sieve set over a 4-quart saucepan, using a silicone spatula to press all of the liquid through; discard any solids. Repeat with the remaining vegetables (including any liquid from the pan) and broth in two more batches.
Stir in the cream and bring to a simmer over medium-low heat. Stir in the vinegar and gently simmer for 5 minutes. Season to taste with salt and cayenne. Remove from the heat and let cool to warm or room temperature.
When ready to serve, heat the remaining 3 Tbs. oil in an 8-inch skillet over medium-high heat until shimmering hot. Add the capers and cook, stirring, until they begin to open like little flowers and become crispy and brown, about 30 seconds. Drain the capers in a small fine-mesh sieve set over a bowl. Transfer the capers to a paper-towel-lined plate; reserve the oil.
Serve the soup drizzled with the reserved caper oil and garnished with the fried capers.