If your pot won't accommodate the turkey, cut the breast halves in half crosswise. We've added a little extra brandy to the dish as it finishes cooking because we like the complexity it lends—for subtler flavor, omit the last 1/2 cup.
Sort and wash beans; place in a large Dutch oven. Cover with water to 2 inches above beans. Cover; let stand overnight. Drain beans.
Split turkey in half lengthwise. Pierce turkey liberally with a paring knife. Place turkey, meat side down, in a 13 x 9–inch glass or ceramic baking dish. Add 1 1/2 cups brandy. Cover and refrigerate overnight. Discard marinade.
Heat a large Dutch oven or stockpot over medium-high heat. Add oil to pan; swirl to coat. Add veal; cook for 10 minutes, browning on both sides. Add drained beans, Turkey-Saffron Stock, 3 cups water, and thyme; bring to a boil. Cover, reduce heat, and simmer for 1 hour and 10 minutes, skimming off and discarding foam as needed. Add turkey and salt. Cover and cook for 35 minutes, skimming occasionally. Add celery and potatoes. Cover and cook for 40 minutes or until thermometer registers 155° when inserted into the thickest part of the breast. Remove turkey; cover with foil. Add remaining 1/2 cup brandy to pan, and cook, uncovered, 20 minutes or until potatoes are tender. Remove thyme; discard. Divide bean mixture evenly among 12 bowls. Slice turkey across grain into thin slices. Divide turkey and veal evenly among bowls.