Japanese nori, a nutrition-rich sea vegetable sold in paper-thin sheets, is used to create nori rolls, or vegetable sushi. The rolls can be made into a seemingly infinite combination of tastes, textures and colors.
Place warm rice in small bowl (rice should be warm, not hot, or nori will shrivel). Sprinkle vinegar over rice; fluff with fork.
Place nori, rough side up, on bamboo sushi mat. With small spatula or dampened fingers, thinly spread rice over entire surface of nori, leaving
Spread umeboshi paste over rice and sprinkle with parsley, gently patting parsley down. Arrange walnuts lengthwise in straight line across center of rice. Lightly moisten the 1/2-inch border at top edge of nori. Be sure bottom edge of nori is lined up with bottom edge of mat.
Place your thumbs under edge of mat closest to you, and your index fingers on walnuts. Roll mat so bottom and top edges of rice meet. Gently press mat around rice. Lift top edge of mat so it doesn’t roll into nori, and continue to roll. Shape nori inside mat; roll may be either round or square.
To serve, place roll, seam side down, on a cutting board. Using damp, serrated knife, slice into 8 pieces; roll may also be cut on diagonal.