Brown veal in oil in a large, nonstick skillet over medium-high heat until seared all over, for about 8 minutes. Stir in flour, onion and garlic, followed by broth. Transfer to slow cooker insert. (Chill overnight if desired.)
Place insert in slow cooker and cook for 8 hours over low heat. Rinse green olives well, cover with water and let soak while veal cooks.
Drain olives, rinse again, then stir into stew. Season with salt and pepper.