What is the secret to very very crispy deepfry?

What is the secret to very very crispy deepfry like in the restaurant? For example is the sweet and sour pork. how do they make it crispy? does draining of oil in paper affects its crispiness?

Tat

The breading has a lot to do with crispy outcome. Whatever batter you use (buttermilk, flour or beer batter like in sweet & sour) batter the meat and then lay it on a cookie sheet and allow the breading to air dry for a while. It begins to look dry (say in chicken, do it about an hour ahead). Then use the correct deep fry temp. Deep fry at 375 in an electric skillet or fry daddy or use a thermometer in a sauce pan. Don’t crowd the pan, fry few pieces at a time. Drain thoroughly and if possible don’t hold too long before serving. (If you put in warm over, it will lose it’s crispyness).

You can bread meat, dry and then freeze. It will be ready for frying when the grease it heated to proper temp.
Cheers