Add oil to a soup pot over medium heat. Add onions and cook for 5 minutes. Add garlic and tomato paste and cook for another 3 minutes.
Add all ingredients to the pot. Stir until butter is melted. Bring to a simmer and cook for 15-30 minutes. Longer is better for flavor but 15 minutes is enough if you want something fast.
Add soup to a blender and blend until smooth. Divide out and serve.
Notes
This makes 2 good servings of soup or 3 smaller ones. You can further thin out the soup with more broth to extend out the servings.