Cover cashews with water and sit overnight to soften. Alternatively, cover them with boiling water and sit for four hours. Cashews need to be well soaked so that when placed in a blender they blend smoothly.

Place oats and water in a high speed blender and blend until smooth.

Strain oat milk through a nut milk bag ensuring you squeeze out all the liquid. Discard remaining pulp into compost or use to make biscuits or oat cakes.

Rinse blender before adding oat milk back into blender with the pre-soaked cashews.

Blend on high speed until very smooth.

Pour into a pot and heat to a simmer whilst stirring. Ensure that the temperature reaches 70C / 160F. Check using a thermometer.

Once the temperature has been reached maintain for at least 15 seconds a to pasteurise. Mixture will be very thick.

Pour thickened oat mixture into a bowl to cool. You can speed up the cooling process by using an ice bath. Stir constantly whilst cooling.

Allow mixture to drop to approximately 43 C / 11oF whilst stirring.

Once mixture has cooled add in the yogurt and gently stir.

Pour into a large thermos or glass jar and screw on the lid.

Keep warm for the next 6-8 hours until the desired tartness is reached. Yoghurt can be kept warm by wrapping in a towel and placing in the sun. Alternatively store in a microwave with a jug of hot water, replacing the water as it cools.

Once tart to taste store into the fridge for up to two weeks.

Now is the time to get creative. Separate your yogurt into jars like this and add different mixes for yummy treats. We love Blueberry and Coriander, Vanilla and Cinnamon and Lemon Cheesecake. Find these recipes in our Fridge Staples section.