Ham, cheese and avocado sushi rolls

1. Rinse and drain rice until water runs clear. Drain in strainer or colander for 15 minutes. Place rice and 1 1/2 cups water in a saucepan on medium heat. Cover and bring to boil.
2. Reduce heat to low. Simmer, covered, for 12 minutes, until water has been absorbed and holes appear on surface. Remove from heat. Stand, covered, for 10 minutes. Fluff with a fork.
3. Spread rice out over a large, shallow glass or ceramic dish. Stir rice with a spatula to break up any lumps. Gradually add vinegar while lifting and turning rice. Cover with a damp tea towel. Set aside to cool.
4. For each nori roll, place one piece of nori, shiny side down, on a bamboo sushi mat. Using damp fingers, spread a quarter of rice over nori. Combine sesame seeds in a bowl. Sprinkle rice with 2 teaspoons of sesame mixture.
5. Cover rice with plastic wrap. Using mat, flip over so nori faces up. Remove mat, then slide plastic onto mat, nori-side up.
6. Spread a quarter of avocado over nori. Arrange a quarter of ham, carrot and cheese along edge closest to you. Roll up sushi firmly, using mat as a guide and being careful not to roll plastic wrap into sushi.
7. Unroll mat, keeping sushi wrapped in the plastic. Use a sharp knife to cut sushi roll into six slices. Remove and discard plastic.
8. Repeat with remaining ingredients to make 24 pieces.