Cook onions until well-cooked. Add celery and continue cooking until onions are browned and celery is cooked. Add garlic and cook for 30 seconds.

Put onion, celery and garlic mixture in a crockpot. Add diced tomatoes, coarse ground tomatoes, diced red pepper and vegetable stock to the crockpot and cook on low for 4 hours.

After 4 hours, cook the orzo.

Blend soup with an immersion blender. Warm the cream and add it to the soup. Add the basil and orzo and serve.