1. In a large plastic container with a lid, whisk together soy sauce, olive oil, 1 cup orange juice, and paprika. Halve the onion and slice half into thin strips. Add the slices to the container. Finely dice the remaining onion half and set aside. Put lid on the plastic container and shake to emulsify the sauce. Set tuna steaks into the container and gently shake to coat. Set tuna and marinade in the refrigerator for 5 min.
2. Meanwhile, chop the bell pepper and pineapple into small pieces and set in a saucepan with the diced onion. Halve the jalapeño, discard the seeds, and chop into small pieces. Add to the pan along with the honey and remaining orange juice.
3. Set grill to medium-high heat and set the saucepan directly on the grill. Close the grill lid and cook for 10–15 min. or until bubbling and slightly thickened. Check sauce and stir occasionally.
4. After 10 min. of cooking the sauce, remove tuna steaks from marinade. Grill the tuna steaks for 5 min. or until grill marks form, flipping halfway. Serve tuna steaks with pineapple sauce.
Per serving: 357 calories, 5g fat, 1g saturated fat, 48mg cholesterol, 442mg sodium, 38g carbohydrate, 3g fiber, 28g sugar, 43g protein