Pour some oil into a wok or large saucepan so it covers the entire base with around 1 cm oil (enough to shallow fry the rings). Make up the batter by first combining the flour, cornflour, salt, turmeric and baking powder in a bowl then mixing gently together.
Add two tbsp of the beer first and mix together. Add in another two tbsp, and combine well until smooth. Add in the remaining beer and mix until no lumps remain and a lovely yellow batter is formed.
Once the oil is hot (test this by adding in a small onion ring that's been dipped in batter and drop it in, if it sizzles away the oil is hot enough). Using a fork, dredge the onion rings one by one in the batter so both sides are evenly covered and fry them in batches of around 5-6 at a time.
Fry on each side until crisp and golden in colour. This should only take around a minute or so on each side. Lay the cooked onion rings on some kitchen towel to remove all the excess oil.
Eat whilst still crisp and warm and enjoy! A perfect accompaniment to hotdogs, burgers or even steak!
