In a large bowl, whisk together the butter, miso, mirin, sake and ginger until dissolved. Add in the shrimp and marinate for 10 minutes.
Cooking on grill: Heat your grill on high heat. Skewer the shrimp onto bamboo skewers. Grill each side for 2 minutes or until cooked through.
Cooking on stove: Heat your grill pan over high heat. Add the shrimp and grill each side for 1 1/2 minutes or until cooked through.
Cooking in oven: Turn your oven to Broil and move the rack to 8" below heating element. Use parchment paper or tin foil on the bottom of baking sheet. Add the shrimp. Broil for 2 minutes each side or until cooked through.