Red Hot Beef Kabobs With Yogurt Sauce

• 1 beef sirloin steak (boneless)
• 240 gr carton low fat (plain)
• 55 gr packed brown sugar
• 38 gr spinach (fresh)
• 32 gr green onions (minced)
• 20 ml cider vinegar
• 16 ml vegetable oil
• 6 gr chili powder
• 5 ml pepper sauce (hot)
• 3 gr salt