In a medium bowl mash together the avocado and Greek yogurt until smooth. Ar

Stir in graduated garlic, onion powder, salt, pepper, and relish until combined.

Stir in tuna fish, red onion, and celery until all ingredients are coated.

Squeeze in lemon juice and stir.

Serve on sandwich or with crackers and vegetables. This tuna salad tastes even better if you can let it for a couple of hours.