Preheat your oven to 375 °F (190 °C).

Wash and cut the tomatoes in half horizontally. Place the tomato halves, cut-side facing up, on a rimmed metal baking sheet. Drizzle with the 2 tablespoons olive oil and sprinkle a teaspoon of kosher salt over them.

Roast the tomatoes on the middle rack of the preheated oven for 50–60 minutes until they are softened, slightly caramelized, and rich in color. Remove from oven and allow to cool slightly.

While the tomatoes roast, heat a large Dutch oven over medium heat. Add a teaspoon of olive oil and sauté the diced shallot until it is soft and translucent (about 3–4 minutes). Add the minced garlic and cook for about 1 minute until fragrant. Then stir in the minced thyme (and if using fresh sage instead of ground sage, add it now).

Transfer the roasted tomatoes into a blender. Add the sautéed shallot/garlic mixture, pumpkin purée, smoked paprika, cinnamon, sugar, sage (if using ground), nutmeg, cayenne pepper, and lemon juice. Blend until very smooth.

Pour the tomato-pumpkin purée back into the Dutch oven. Stir in the vegetable broth (use more broth if you prefer a thinner soup). Bring the mixture to a gentle boil, then reduce heat and heat through until piping hot.

Taste the soup and add additional kosher salt as desired (about 1–2 teaspoons total depending on your broth and preference).

Serve the soup hot in bowls. Drizzle with a little heavy cream (optional) and olive oil. Top with pepitas (pumpkin seeds), fresh basil leaves, and freshly ground black pepper.