For the dip place all the ingredients into a bowl and mix together. Set aside for serving.
Cut off top of onion and remove skin. Sit on flat top to keep stable. About ½ an inch away from the root make 12 even cuts down to the chopping board, like a clock face.
Make sure to keep the root intact, this will hold the onion together while it is frying.
Turn the onion over and remove any of the centre that may have come loose. Gently open the petals like a flower.
Mix the flours and seasoning spices in a large bowl and set aside.
Whisk buttermilk and eggs together in a separate bowl and set aside.
Pre head oil in large pan, or set deep fryer to 180°C.
Gently place onion root side down into the dry seasoning mix. Spoon seasoning over the onion, ensuring an even coating. Gently shake off any excess.
Place the onion root side down in the buttermilk mix. Spoon mix over the onion, ensuring all petals are coated.
Place the onion back into seasoning mix and ensure all petals are coated in flour. Shake off any excess.
Place the onion on to a tray root side down, open the petals up and place in the freezer for 2 hours to set. This will help the onion keep its shape when you fry it.
Using a large spoon and a pair of tongs gently lower the onion into the hot oil root side down.
After 2 minutes gently roll the onion in the oil so the root side is down and continue to fry for a further 7 minutes.
Once golden brown and crispy, gently remove the blooming onion from the hot oil allowing any excess oil to drip off. Place petal side up onto kitchen towel to drain.
Place onto a plate with all the petals facing up and serve with the dip.