Season calamari with salt and pepper. Marinate in Spicy Red Chimichurri Sauce for about 1 hour. Remove from marinade, place on hot grill and cook until grill marks show on both sides. Toss mizuna greens with olive oil and lemon juice.
Arrange calamari on plate with mizuna greens. Drizzle with the balsamic reduction.
Spicy Red Chimichurri Sauce:
Place all ingredients in food processor and pulse until pureed.