Rinse 1 cup of sushi rice under cold water until the water runs clear. In a medium saucepan, combine the washed rice with 1 ¼ cups of water and bring to a boil. Reduce heat to low, cover, and simmer for 20 minutes. Remove from heat and let it cool slightly.

In a small bowl, mix 2 tablespoons of rice vinegar with 1 tablespoon of sugar and ½ teaspoon of salt until dissolved. Once cooled, gently fold this mixture into the sushi rice.

Mash 1 ripe avocado in a bowl until creamy, then add in ½ cup of diced cucumber and 1 tablespoon of lime juice. Mix until well combined.

In another bowl, combine 1 cup of diced cooked shrimp, 2 tablespoons of mayonnaise, and 1-2 tablespoons of sriracha, stirring until shrimp is evenly coated.

Layer the stacks using a round mold: start with 1/3 cup sushi rice, press down, add the avocado and cucumber mixture, then the spicy shrimp. Repeat until the mold is filled.

Carefully remove the mold and sprinkle the top with furikake. Serve immediately.