Put the porridge oats in a bowl and cover with tap water until the oats are submerged. Cover the bowl (a shower cap or teatowel work well) and leave for 4 hrs or overnight, somewhere cool, but not in the fridge.

Sieve the mixture, discarding the water, and rinse under the tap for a few seconds.

Tip the oats into a liquidiser, or food processor. Cover with 750ml cold water and 1/2 tsp fine sea salt. Blend for 2-4 mins until completely smooth, and there are no oats visible. The finer you make the mixture, the creamier the milk will be.

Line a sieve with a clean piece of muslin, or a cloth with a mesh – it needs to have small holes, so a j-cloth or teatowel might not work. (You could also try a fine strainer or meshed coffee filter.)

Put the lined sieve over a bowl or jug, and pour in the oat milk. Leave to strain for 1 hr. Every once in a while, use a spoon to scrape the bottom of the cloth to disperse some of the sediment, this will help speed up the straining.

When most of the liquid is in the jug, gather the sides of the muslin together and squeeze tightly with both hands to extract the last of the milk. Discard leftover oat pulp (or make a body scrub by adding used coffee grounds).

If you want thinner consistency, add 50ml cold water to the mix, before pouring into a bottle or container. See our troubleshooting tips below. Will keep for 2-3 days in the fridge. Shake well before use.