Divide halibut fillet into approximately 1.5" cubes.
Mix dry ingredients, add beaten egg. Pour beer in until proper consistency. Batter will be smooth and a little runny but thicker than water.
The remaining beer is yours to enjoy.
Add oil to frying pan until oil is approximately 1/2 the height of the halibut cubes; heat on medium high until suitable for deep frying.
Make a test piece:.
Coat halibut piece in batter, add to oil. Fry for two minutes, then turn with tongs (being very careful of oil spattering) and fry another two minutes. Transfer finished piece to a paper towel covered plate. Split piece with fork to check for doneness, if piece does not split easily and/or middle of halibut piece does not appear to be opaque, adjust cooking time and/or oil temperature to ensure pieces are done.
When satisfied with cooking time, repeat until all pieces have been cooked (multiple pieces can be put in pan).
Serve warm with tartar sauce.