Cook the rice according to the instructions on the package. Season the rice with salt and sushi vinegar. Divide the sushi rice over 4 glasses.
Meanwhile, press the garlic. Mix the prawns with the sesame oil and garlic. Season with salt to taste. Heat the grill pan and grill the prawns on a high heat in about 3 minutes until they are pink and cooked.
Slice the beetroots into 1 cm cubes. Season with salt and pepper. Divide over the sushi rice.
Cut the avocados all the way around the stone. Twist the two halves apart. Remove the stone, scoop the flesh out of the skin with a spoon and cut into cubes. Season with salt and pepper. Divide the avocado over the beetroot. Drizzle with soy sauce.
Divide the prawns over the avocado. Scatter with the sesame seeds.
Tip: You can also prepare this dish in advance. Cook the rice (also tasty at room temperature), marinate the prawns and slice the beetroot. Grill the prawns and slice the avocados just before serving. Then assemble the dish.
