Sweet-and-Sour Pork Meatballs with Pineapple

Name: Sweet-and-Sour Pork Meatballs with Pineapple
Prep time: 45 min
Total time: 45 min
Cuisine: Asian
Ingredients: 1 lb. ground pork; 1/2 small onion, finely diced; 1 large egg; 1/2 c. breadcrumbs; 1/2 tsp. crushed red pepper flakes, plus more to taste; 1 tsp. kosher salt; Black pepper, to taste; 1 1/2 c. beef broth; 1/2 c. white wine vinegar; 1/3 c. sugar; 2 tbsp. soy sauce; 2 tbsp. cornstarch; 1/4 c. vegetable oil, for frying; 1/4 c. all-purpose flour; 2 red bell peppers, chopped; 1 1/2 c. fresh pineapple chunks; 2 scallions, sliced; Cooked white rice, for serving