Heat oil in a small saucepan over medium-high heat. Add ginger and garlic; sauté 2 minutes. Stir in wine, tamari, brown sugar, and spice mix; remove from heat. Stir in peanut butter. Set aside; keep warm.
Prepare grill. Cut tuna steaks into 20 (1-inch) pieces. Thread tuna and artichokes alternately onto each of 4 (12-inch) skewers. Place kebabs on a grill rack coated with cooking spray; grill 3 minutes or until desired degree of doneness, turning and basting with peanut sauce. Serve with Shanghai Spinach Rice; garnish with cilantro, if desired.