Portabello Onigirazu

Portabello Onigirazu, a Japanese sandwich made with roasted Portabello mushrooms and savory rice, is a delicious dish for lunch or as a snack.
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Prep Time 20 minutes
Cook Time 20 minutes
Course Culinary Collection, Lunch
Cuisine Asian, Japanese, South African
Servings 4


For the rice

  • 400 g sushi rice
  • 500 ml water
  • 2 tsp salt
  • 2 tbsp sugar
  • 160 ml rice vinegar

For the filling

  • 1 tbsp sesame oil
  • 4 large portabello mushrooms thickly sliced
  • 1 tbsp soy sauce
  • 8 sheets nori
  • 1 large avocado quartered and sliced
  • 1 large carrot peeled and sliced into fine matchsticks
  • ½ small cucumber sliced
  • 1 handful baby spinach leaves
  • 4 tbsp pickled ginger

To serve

  • black sesame seeds
  • soy sauce for dipping


For the rice

  • Rinse the sushi rice in a sieve, extremely well, until the water runs clear.
    Pour the rinsed rice into a pot with the 500ml water.
  • Place a lid on the pot.
    Allow to sit for 30 minutes.
  • Place rice onto the heat and bring to a boil.
    Once rice reaches a boil turn the heat down to the lowest setting.
    Cook for 10 minutes.
  • Switch the heat off and leave the rice, lid on, for a further 15 minutes.
    In a small saucepan, combine the salt, sugar and rice vinegar over low heat.
  • Once dissolved, pour evenly over the rice and fold very gently with a wooden spoon or silicone spatula.
    Spread rice out onto a clean tray and allow to cool.

For the filling

  • Heat a large frying pan on high heat.
    Add a drizzle of sesame oil and the mushrooms.
  • Cook until just golden brown and tender.
    Pour in the soy sauce and toss to coat.
    Set aside.
  • Prep the rest of the vegetables.

To assemble

  • Lay a nori sheet (rough side up) on a clean work surface.
    With wet fingers to prevent sticking, position ± ½ cup of the cooked rice in the centre of the nori sheet and shape it into a square, at a 45˚ angle to the nori.
  • Layer the baby spinach, carrot, pickled ginger, avocado, mushrooms and cucumber.
    Put another ± ½ cup layer of rice on top of the filling, and compact it down into a square.
  • Fold the corners of the nori in to meet in the centre of the rice, then wrap in the plastic wrap tightly and shape neatly.
    Repeat with the remaining rice and fillings.
  • *** Top tip:
    You should only need one sheet of nori per sushi sandwich, however if you overfill them just use a piece of another sheet and patch the sandwich until it seals nicely.
    Leave each onigirazu wrapped for 10 minutes so the nori softens slightly.
    Slice in half and sprinkle with black sesame seeds.
    Serve with some soy sauce for dipping and enjoy!
Keyword lunch