Sweet Potato and Shiitake Rolls

I enjoy sweet potatoes in almost any form, especially when the flavor is sweet and salty. As an alternative to boiled sweet potatoes, try Soy Glazed Sweet Potatoes.

Rice Prep Time: Up to 1½ hours
Sushi Prep Time: 30 minutes
Makes 4 rolls (20 pieces)

1½ cups (375 ml) water
1 cup (250 ml) soy sauce
4 tablespoons mirin or sherry
½ small sweet potato, peeled and cut into chopstick-width lengths
4 large shiitake mushrooms, wiped and stems removed
Four 4 x 7-in (10 x 18-cm) nori sheets
3 cups (600 g) Traditional Sushi Rice, Brown Sushi Rice, Quinoa Sushi “Rice” or Multi-Grain Sushi Rice
2 oz (60 g) daikon radish sprouts (kaiware) or pea sprouts
4 teaspoons slivered almonds, toasted

Bring the water, soy sauce and mirin to a boil in a saucepan. Add the sweet potato pieces and cook until soft, about 3–4 minutes. Remove and allow to cool and drain on paper towels, reserving the cooking liquid for mushrooms. Add mushrooms to the liquid. Reduce heat and simmer for 5 minutes. Remove mushrooms. Pat dry and allow them to cool, then slice them into thin strips.
Place a 4 x 7-in (10 x 18-cm) sheet of nori vertically on a bamboo rolling mat. Make sure that the short end is parallel to the bottom of the mat and that the rough side is facing upwards.
Dip your fingertips lightly in cool water and spread about ¾ cup (150 g) of the sushi rice evenly over the bottom ¾ of the nori. Arrange ¼ of the sweet potato pieces horizontally across the middle of the rice, making sure that they extend to both edges of the nori. Add ¼ of the mushroom pieces and daikon sprouts. Sprinkle 1 teaspoon of the almonds over the top.
Wet your fingers again and slide your thumbs underneath the mat while grasping the fillings with fingertips. Roll the bottom of the mat just over the fillings, tucking the fillings tightly under the fold. (Do not allow the mat to get stuck inside the roll!)
Lift the edge of the mat. Continue rolling until the roll is complete and the seam is facing down. Gently shape the roll by pressing your forefingers on top of the mat while simultaneously pressing your thumbs and middle fingers on the sides.
Allow the roll to rest seam-side down on a cutting board for at least 2 minutes. Repeat to make 3 more rolls.
To cut the rolls, dip the blade of a very sharp knife in water. Use a swift sawing motion to cut each roll into 5 pieces.