For light and fluffy, with that crisp outer texture, I use a home-made tempura batter. It's simple, cheap, and can be modififed so many ways. Here's the one for fish.
Dry the fish with a paper towel. Heat oil in a deep, large pot, or in your deep fryer to 360' F. Or, if you are going to pan fry the fish, heat 3 inches of oil until fragrant.
Dry Ingrediants:
1/2 cup white flour
1/2 cup cornstarch
1/2 tsp. salt
1 tbs. sugar
3 tsp. double-acting baking powder
1 large egg
3/4 cup water
Combine all dry ingrediants with a whisk. Add the egg and water. Whisk until the batter is smooth. Dip the fish into the batter and fry until golden brown. You won't be dissapointed. Serve with a lemon sweet and sour sauce.
Lemon Sweet and Sour Sauce
Ingrediants:
12 oz. water
1/4 cup sugar
3 tbs. Lemon Juice
Yellow food coloring
2 tbs. cornstarch
Combine water, lemon juice, sugar, and a couple drops of yellow food coloring. Bring to a boil. Taste the mixture after letting it cool on a spoon. If it isn't strong enough, add 1 more tbs. sugar and another tbs. lemon.
Continue the process until the liquid is sweet & tart enough for you taste. With the fish, you may not want it as sweet so play with the amounts of lemon and sugar.
When you get the flavor you want, mix the cornstarch with 2 tbs. cornstarch and add to the boiling liquid. Stir vigorously, taking care to not splash yourself with the hot liquid. Serve over the tempura fish.
The tempura batter can be made more savory or sweet, depending on what you are coating. For fruits, add more sweetener. For something like chicken, add garlic powder, onion powder, and sage or thyme to the batter, or replace the water with chicken broth. You can really do a lot with this batter with a bit of imagination. Enjoy.
Seeeeeya; Goodweed of the North