Mix together the boiling water and bouillon in a medium saucepan and set over a low heat to simmer. Place a second medium saucepan over a medium heat and add the olive oil and bring to temperature.
Once your oil is hot, add the diced onion and cook for two minutes or until turning translucent. Add the garlic and cook for another 2 minutes.
Add the rice and stir to combine with the onion and garlic. Allow the rice to heat lightly for around a minute before adding your wine and stirring again.
Once almost all of the wine has evaporated, us a ladle to spoon some hot bouillon (which should be still simmering) and pour over the rice while stirring constantly. Allow the rice to cook off most of the moisture and then add another ladle full of bouillon. Repeat until you have no bouillon remaining (around 10-15 minutes).
After all the bouillon is gone, check the rice is done by tasting a small amount. If it feels gritty in the centre it's not done, but if it feels smooth but very slightly firm, then you're done. If the rice is not cooked, add a few more ladles of boiling water and continue to cook until it is.
Once the rice is fully cooked, remove from the heat and stir in the lemon zest and nutritional yeast. Spread the risotto out on a baking tray to allow it to cool for at least an hour in the fridge, or, if you're not in a rush, cover it up and allow to cool overnight.