If you’re looking to create something unique and spectacular, then you have to try this delightful Portabello Onigirazu recipe.

These sushi sandwiches are slightly different from the more traditional onigiri sandwiches.

Whili onigiri is more of a sushi sandwich with traditional fillings, onigirazu can contain a range of fillings, and is best described as a rice sandwich.

Of course, there are dozens of different onigirazi recipes and onigirazi filling ideas – you can include anything from sushi ingredients to traditional sandwich toppings.

This portabello version is a vegetarian onigirazu recipe and makes four rice sandwiches.

Let’s look at how to make vegetarian onigirazu!

Onigirazu Recipe Ingredients

To make onigirazu rice:

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

To make the vegetarian onigirazu 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:

How To Make Onigirazu – Method

How to make onigirazu sushi rice:

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

How to prepare the onigirazu filling:

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

To assemble onigirazu rice sandwiches:

  1. Lay a nori sheet (rough side up) on a clean work surface.
  2. 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.
  3. Layer the baby spinach, carrot, pickled ginger, avocado, mushrooms and cucumber.
  4. Put another ± ½ cup layer of rice on top of the filling, and compact it down into a square.
  5. Fold the corners of the nori in to meet at the centre of the rice, then wrap it tightly in the plastic wrap tightly and shape it neatly.
  6. Repeat with the remaining rice and fillings.
  7. 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.
  8. Leave each onigirazu wrapped for 10 minutes, so the nori softens slightly.
  9. Slice in half and sprinkle with black sesame seeds.
  10. Serve with some soy sauce for dipping and enjoy!

Portabello onigirazu recipe

Portabello Onigirazu Recipe Notes

This Portabello Onigirazu recipe is courtesy of the South African Mushroom Farmers’ Association (SAMFA), a group of farmers who grow and love mushrooms.

They share their passion by promoting all varieties of mushrooms, creating unique recipes that showcase the many flavour profiles of mushrooms, and engaging in charity campaigns that make the world a better place.

Why mushrooms?

These powerful little foods are packed with nutrients and fibres, have very few calories, and are an excellent source of plant protein. If spiced right, they even make a great meat replacement!

You can check out SAMFA’s social media pages on Facebook, Instagram, and Twitter for all their latest updates.

We’ve shared dozens of SAMFA recipes, which you can access in our full Recipes Archive. You may just find your next delicious meal there!

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