Line a large pot with a thin layer of vegetable broth, and sauté onion and garlic over high heat until onions start to become translucent, about 2 minutes. Add carrots, celery, and remaining broth and bring to a boil.
Once boiling, reduce to medium, cover, and keep cooking until carrots are softer but still firm, about 5 minutes. Add 1 tbsp fresh thyme, 1 tbsp fresh parsley, diced tomato, and tomato paste, stirring to combine. Continue to cook until carrots are fork-tender and soft, but not mushy or falling apart--about 4 more minutes.
Stir in beans (with liquid) until well-combined and add remaining fresh thyme and parsley. Reduce heat to low and cook until beans are warm. Ladle into a bowl and garnish with a thyme sprig.