Sauté the finely chopped onion in a large pot or Dutch oven with olive oil until slightly browned.
Add minced garlic, diced celery, and chopped carrots. Sauté for about ten minutes until they soften and brown slightly.
Pour in the white grape juice and sauté until most of the liquid evaporates, about five minutes.
Add all remaining ingredients except for the kale. Stir well and adjust broth based on desired thickness.
Bring to a boil, cover, and reduce heat to low. Let it simmer gently for about fifteen minutes.
Discard bay leaves and transfer about two and a half to three cups of soup into a blender. Blend until smooth.
Pour the blended mixture back into the pot and stir. Adjust thickness with more broth if needed.
Add chopped kale and simmer for a few more minutes until wilted. Adjust flavors with salt, pepper, or lemon juice.
Serve warm on its own or with hearty bread on the side.