Sushi-Roll Salad

Ingredients

• 1 tablespoon rice vinegar
• 1 teaspoon canola oil
• 1 teaspoon low-sodium soy sauce
• 1/2 teaspoon wasabi paste
• 1/2 avocado, peeled, pitted, diced
• 1/2 cup cooked brown rice
• 1 cup baby spinach
• 1 5-oz. can solid white tuna in water, drained, large pieces broken up
• 1/2 cup diced cucumber, peeled if desired
• 2 scallions, cut on the diagonal
• Salt and pepper, optional