Cilantro Steak in Lettuce Cups

WHAT YOU'LL NEED

• 1 cup Italian dressing
• 1 Tbsp. lime juice
• 2 Tbsp. chopped fresh cilantro
• 1 1/4 lbs. sirloin steak
• 3 portobello mushroom caps or 2 cups white mushrooms
• 1 large red onion, cut into wedges
• 1 medium red bell pepper
• 1/4 cup sour cream
• Iceberg lettuce cups
• 1 package Knorr® Rice Sides™ - Cheddar Broccoli, prepared according to package directions