Prepare tuna salad by combining 1 can drained tuna with 2 tbsp mayo, 1 tsp lemon juice, and 1 tbsp finely chopped celery or onion
Season tuna salad with salt and pepper to taste
Fill a cupcake pan with cooked sushi rice, pressing gently to form cups
Top each rice cup with a portion of tuna salad
Add small avocado slices on top
Drizzle with sriracha sauce
Sprinkle with black and/or white sesame seeds
Serve chilled or at room temperature
