Liberally season your Mackerel fillets with Old Bay. This could be done up to a day in advance, or as little as an hour before - the seasoning helps firm up the fish which is preferable for this style of cooking.
Start your fire.
Whilst your fire is in its initial burn stage; lay your herbs onto your cedar plank, followed by your seasoned mackerel fillets.
Use your annular nails and hammer to carefully pin the fillets to your plank; leave a little of the nail head out so they’re easy to remove once your fish is cooked.
Move your fire to one side and add another log to creat some smoke.
Place your cedar plank upright in the path of your fires smoke - this indirect heat will slowly cook our fish.
Whilst your mackerel is getting is first kiss of smoke. Combine the ingredients for your Cajun glaze in a bowl and give a good whisk.
Our mackerel now should be showing signs of cooking. Flip your cedar plank 180degrees so each fillet gets an even cook.
Now we can apply our glaze, liberally with a brush to our mackerel fillets.
Continue with this process until your mackerel is cooked through - should be roughly 30 minutes, or until your your fillets hit 58 degrees with a temperature probe.
Remove your plank from the fire place and allow to rest for a couple of mins.
Ensure to remove all the nails before serving; they don’t taste very nice!
