Preheat oven to 425 F.
Wash and cut tomatoes into halves, quarters, or sixths (depending on size). Cut out tough center cores as needed. Leave cherry tomatoes whole. Leave skin and seeds in place.
On a lined baking tray (e.g. parchment paper) place cut tomatoes skin-side down in a single layer. Add peeled whole garlic cloves and optional sliced bell pepper. Drizzle with olive oil, sprinkle with salt and pepper.
Roast tomatoes, garlic, and optional bell pepper in the oven for 40-45 minutes, until soften and golden brown to lightly blackened in some spots.
While the tomatoes are roasting, prep and cook the celery, onions, and carrots.
Add olive oil to the bottom of a stockpot or sauce pan over medium heat on the stovetop. Once warm, add chopped onions, celery, and carrots. Sprinkle with salt and pepper. Simmer over medium-low heat until the onions become translucent, and the carrots and celery soft (about 15-20 minutes). Stir occasionally. Cover and remove from heat until the tomatoes are done roasting.
Carefully transfer the roasted tomatoes (and other pan contents/juices) to the pot.
Add all of the other called-for ingredients: vegetable broth, coconut milk, chopped fresh basil (or dry), and remaining seasonings: Italian seasoning, paprika, cumin and optional allspice and/or coriander. Allow the mixture to return to a low boil, stirring occasionally.
Use an immersion blender to puree the soup until smooth right in the pot. Or carefully transfer the roasted tomato basil soup into a regular blender to puree in batches as needed.
Taste, add more salt and/or pepper if needed. If a thicker consistency is desired, simmer longer to reduce and thicken.
Serve and enjoy!
Store leftovers in the refrigerator and enjoy within one week.
Freeze extras in freezer-safe containers for up to one year (6 months for best quality).