Rinse the sushi rice very well to remove the starch, around 7 times.

Drain the rice and add it to a pot with a tight-fitting lid.

Add in the water, a pinch of salt put on the lid, and heat on high until starting to boil.

Lower the heat to the lowest setting, and let cook for 15 minutes (covered).

Remove from the heat and let sit for five minutes.

Microwave the vinegar, salt, and sugar together, for one minute stirring halfway, then stir when done until the salt and sugar has dissolved

Add the oil to a large wide skillet or frying pan and heat on high. Add the tofu strips and let cook for one minute.

Flip the strips to an unbrowned side and let sit for 30 seconds. Repeat twice more until all sides are golden brown (honestly I just do three sides!).

Mix together the sweet chili sauce and the vegetable stock and add to the pan. Reduce the heat to medium-high when the mixture starts bubbling.

Cook for between 6 - 10 minutes, tossing gently to coat the tofu with the sauce until it has thickened and any remaining sauce just coats the tofu. Put to one side to cool.

Set out a bamboo mat for rolling the sushi. If you don’t have a mat, a slatted placemat or a sheet of baking paper will do in a pinch. Thinly slice the onion and the avocado. If you don't like raw onion or find it too strong I would suggest soaking it in salty water for between 10-15 minutes (ideally do this earlier, for example when you are making the sushi rice).

Lay a sheet of nori on top (shiny side down) and put roughly half a cup to two-thirds of a cup of sushi rice on it.

Using wet fingers spread out the rice so that the nori is covered in a single layer with no spaces, leaving a centimeter of nori free for sealing the roll at the top edge furthest away from you.

Place your filling ingredients just below the middle in a horizontal line. Lay the strips of onion, then the strips of avocado, then the sushi strips (just join them up if they are not long enough or break them up if they are too long).

Dampen the rice-free nori edge with a little water, grab the mat close to you, lift up the mat and tuck it over quickly the filling to secure it, and continue to tightly roll with pressure from both hands until the dampened end is underneath (seam side down).

Repeat for all the rolls.

Using a sharp knife, wet it to stop it from sticking to the nori and slice each sushi roll into eight evenly sized pieces.

Serve immediately or leave to chill in the fridge until you're ready to eat.