Start by sifting the flour, cornstarch, baking soda, baking powder, and salt together into a mixing bowl.
Next, add the water to the dry ingredients and mix everything together until you have a smooth batter.
Take your fish or chicken filets and coat them completely in the batter.
Heat up some oil in a deep frying pan or pot until it’s hot enough for frying.
Carefully place the coated filets into the hot oil and fry them until they turn a nice golden brown on both sides.
Remove the filets from the oil using a slotted spoon or tongs and place them on a paper towel-lined plate to drain any excess oil.
Serve your crispy, golden fried fish or chicken filets with your favorite dipping sauce and enjoy