Slow-Cooker Sweet & Sour Scallops

Whisk together the ketchup, orange juice, vinegar, cornstarch, soy sauce, and salt in a small bowl; pour into a 5- to 6-quart slow cooker. Add the pineapple, bell pepper, onion, and jalapeno to the slow cooker. Cover and cook on LOW until the vegetables are mostly tender, about 4 hours. Add the scallops, and stir to combine; cover and cook until the scallops reach the desired degree of doneness, about 8 minutes for medium. Divide the brown rice among 4 bowls. Serve the scallops and sauce over the brown rice; garnish with the scallions, if desired.