I've eaten these recently, in Shabu-shi in Mega Bangna shopping mall. Calling them shrimp in breadcrumbs doesn't really describe them, they're very very long shrimp in breadcrumbs.
The shrimp are stretched out, and padded with flour and breadcrumbs, so they appear to be very much longer than they are. It takes some practice to turn a short one into a long one, but with shrimp being expensive this is a great way of padding them.
8 Large Shrimp
All Purpose Flour or Tempura Flour
Pinch of Salt
1. I've found two ways they are made, concertina and cut-in-half. Start by shelling the shrimp, leaving just the tail segment in place.
2a. Concertina fashion, making cuts into the shrimp above and below alternately. The shrimp can be stretched out to a long thread. Don't pull it longer by the ends, it will break, instead, squeeze any fat sections between your fingers to make it longer, and press to straighten out the shrimp where there are cuts.
2b. Cut along the back starting from the tail, and towards the head, but stop short of the head. I found I could cut down the back and this method was easier for removing the black gut and back vein.
Fold out the half and press the end with your fingers to flatten the join. You've made it twice as long! It's more difficult to keep it straight in the pan using this technique, so you may need to hold it straight as you fry it, but it's a lot easier.
3. Once you've got your lengthened shrimp, prepare three plates, one with breadcrumbs, one with flour seasoned with the salt, one with blended egg.
4. The shrimp should be coated in the flour, then coated in the egg, then coated in the breadcrumbs.
5. Fry in medium hot oil until golden.
6. Serve with a tempura dipping sauce, or better still, Thai spicy chilli sauce.