Hawaiian-Style Short Ribs

INGREDIENTS

• 2 red onions, cut into 1-inch wedges, root ends left intact
• 4 garlic cloves, smashed
• 2-inch piece fresh ginger, peeled and thinly sliced
• 4 pounds bone-in beef short ribs (about 6), cut in 3 1/2-inch pieces
• 1 1/2 cups dark-brown sugar
• 1 cup low-sodium soy sauce
• 6 tablespoons rice vinegar
• 1 tablespoon Sriracha or other chili sauce
• 3 cups 1-inch-cubed pineapple (1 pound)
• Cooked white rice, for serving
• Chopped scallion greens, for serving