Heat in large skillet; oil, onion, celery, carrot, pepper, and garlic. Saute until tender. Stir in tomatoes, chili powder, tomato paste, vinegar and pepper. Cover, reduce heat, and simmer 10 minutes. Stir in kidney beans and cook an additional 5 minutes. Serve on kaiser rolls, or buns.
I topped with shredded cheese and a little bit of BBQ sauce to add a little sweetness.