Combine flour, salt and pepper in a shallow dish. Dredge each chicken breast until covered.
In a large skillet, heat 2 tsp of olive oil. Sauté onion until tender. Remove from pan and set aside
In the same skillet, brown chicken on all sides.
Combine tomato sauce, broth, paprika, sugar, bay leaf and onion; pour over chicken. Cover and simmer for 30-40 minutes or until chicken is cooked through.
Remove chicken to a platter and keep warm. Reduce heat to low; remove bay leaf and stir in sour cream. Heat through for 2-3 minutes (do not boil). Pour over chicken and serve.
