Pulse the oats in a food processor until you get a coarse flour. Add the plain flour, rice flour and cornflour as well as the baking powder, salt and sugar to the food processor and blend to combine. Tip the contents of the food processor into a medium bowl.

Turn your waffle iron on now so that it can preheat. Get some vegetable oil ready for spraying/brushing onto the waffle iron. Place a wire rack over a baking tray and set aside.

Combine the soy milk, vinegar, olive oil, flax seed and vanilla extract in a jug. Pour this all into the bowl of dry ingredients. Use a whisk or a mixing spoon to combine into a mostly smooth batter.

Grease your waffle iron with some neutral vegetable oil (I use a heatproof silicone pastry brush to do this but you can use a spray oil if you have it). Scoop some of the waffle batter into your waffle iron (I use 1/3 cup per waffle for my iron but the amount will vary from brand to brand). Close the lid and cook until golden brown on both sides - this takes around 4 minutes for me. You can usually tell when the waffle is almost ready by noticing that less steam is coming out of the waffle iron.

Use a fork or butter knife to prise the waffle out of the iron and place onto the wire rack on the baking tray - this prevents trapped steam under the waffle making it soggy! Either eat warm as they come out of the waffle iron or place the tray with the wire rack of waffles into a low oven to stay warm as you cook the rest of the waffles.