Add the rinsed rice and water to a saucepan or rice cooker. Cook until the water has been absorbed and the rice is tender, about 20 minutes.

Combine the rice vinegar, sugar, and salt in a small saucepan over medium-low heat. Stir until the sugar and salt have dissolved.

Once the rice has cooked, pour the vinegar mixture over, and gently fold in. The rice should be sticky, not wet.

In a mixing bowl, whisk the egg until it's well beaten

Slowly add the ice-cold water to the beaten egg, continuing to whisk until it's fully incorporated. Add the flour, stirring lightly to combine.

Heat the vegetable oil in a deep pan or fryer to around 350°F (175°C)

Dip the soft-shell crabs in the tempura batter, coating lightly on all sides

Carefully place the coated crabs into the hot oil. Cook for 3-5 minutes until golden and crispy. Remove from oil and rest on paper towels to cool and drain excess oil.

Lay a sheet of nori seaweed on a bamboo sushi mat. Spread ½ cup of sushi rice over the nori, leaving a 1-inch border.

Arrange the fried crab, avocado, cucumber, and fish roe in the center of the rice.

To roll the sushi, lift the edge of the mat closest to you and start rolling away from your body, using your fingers to compact the ingredients as you go. Once you reach the end of the nori, wet the 1-inch border with water and finish rolling.

Cut the sushi rolls into 6-8 pieces, wiping your knife between each use to ensure effective slicing

Serve with soy sauce, wasabi paste, and pickled ginger.