• Combine the uncooked white rice and ½ cup water in a bowl. Let the mixture sit for about 10 minutes.
• Add the lean ground beef, diced onion, salt, celery salt, garlic powder, and black pepper to the rice mixture. Mix until all of the ingredients are combined. Form the mixture into evenly sized meatballs. Try to keep them similar in size so they cook at the same rate.
• Heat a large skillet or Dutch oven over medium heat. Add the meatballs and brown them on the outside, turning carefully as needed.

  They don’t need to be completely cooked through at this point because they will continue cooking in the broth.
• Pour the 2 cups of broth over the browned meatballs.

  Cover and simmer for 45 to 60 minutes, or until the meatballs are no longer pink in the center, reach a temperature of 160°F, and the rice is tender. 

Sauce

• While the meatballs are cooking, drain the pineapple, reserving the juice. Set the pineapple chunks aside.

  Add the pineapple juice to a bowl and whisk in the cornstarch, brown sugar, vinegar, and soy sauce until smooth.
• Melt the butter in a non-stick pan over medium heat.

  Add the chopped green pepper and onion. Sauté for about 4 to 5 minutes, or until the vegetables are crisp-tender.
• Pour the pineapple juice mixture into the pan with the vegetables. Cook over medium-low heat, stirring frequently, until the sauce thickens and becomes syrupy.
• Pour the thickened sweet and sour sauce over the cooked meatballs. Carefully stir in the reserved pineapple chunks. Let everything simmer together for about 10 minutes so the meatballs can absorb some of the sweet and tangy sauce.