Makes: 6 servings at $3.09 each. Prep Time: 25 minutes. Refrigerate: 30 minutes. Cook: 40 to 45 minutes. Grill: 4 to 6 minutes.
Whisk together the vinegar, raspberry preserves, salt and pepper in a small bowl until the salt is dissolved. While whisking slowly, drizzle in the olive oil and continue to whisk until the dressing is well blended and thick. Cover the dressing and set aside until ready to use, or refrigerate if making the salad later in the day.
Pour one quarter of dressing into plastic food-storage bag. Add the tuna and seal the bag; turn to thoroughly coat the tuna. Refrigerate and let marinate 30 minutes.
Cook the wild rice and white rice separately, following the package directions for each. Spread the rices out separately on 2 large baking sheets to cool.
Prepare outdoor grill with hot coals, or heat gas grill to hot, or heat oven broiler.
Remove the tuna from the marinade; discard the marinade. Season tuna with salt and pepper.
Grill or broil the tuna for 2 to 3 minutes on each side for medium. Set aside to cool.
Mix together the wild rice, white rice, celery, scallion and asparagus in a large bowl. Pour in the remaining dressing; gently toss to coat all the ingredients evenly.
Flake the tuna; gently fold the tuna into the rice mixture.
To serve, make bowls with individual Bibb lettuce leaves. Equally divide the tuna salad among the leaves. Or, line a large serving bowl with the lettuce leaves; spoon the salad into the bowl.