1. Wash the rice well and place in a saucepan with the water and bring to the boil. Cover and simmer for 12 minutes. Remove from heat, stand for 10 minutes.
2. Mix in the sushi vinegar.
3. Place one sheet of nori on a bamboo sushi mat and spread about 2 handfuls of rice on top of the nori, leaving one edge with a 2 cm strip, free of rice.
4. Spoon a thick line of the HEINZ [SERIOUSLY] GOOD™ Mayonnaise down the center and then top with a generous serve of Greenseas Sundried Dried Tomato & Basil Tuna. Arrange a few slices of carrot, cucumber and avocado on top.
5. Using the bamboo mat as a guide, roll up the sushi to firmly enclose the filling. Repeat with the remaining ingredients. Cut into 2 cm wide slices and serve with wasabi or pickled ginger if wished.