Cook the rice: Prepare the microwavable rice according to package instructions. While hot, option to mix in the rice vinegar. Add to aline loaf pan and press firmly to create a 1-inch thick layer. Press firmly. Refrigerate for 1-2 hours.
Chill and air fry: Remove the rice from refrigerator and cut into 1″ x 1 1/2″ slices. Preheat your air fryer to 390°F (200°C). Once preheated, arrange the rice cakes in a single layer and cook for 7-9 minutes, or until golden brown and crispy.
Prepare the topping - Tuna version: Food process the carrots until finely chopped. Combine the mashed carrot tots and chopped carrots in a bowl. Mix the sliced tuna with vegan mayo and sriracha to your desired spice level.
Prepare the topping - Vegan version: Mix the vegan mayo, sriracha, choped carrots and tots together in a large bowl.
Assemble and enjoy: Arrange the crispy rice cakes on plates. Top each with avocado slices, followed by your prepared tuna or vegan "tuna" mixture. Garnish with avocaodo and optional toppings and enjoy!