Someone told me about a dish with consists of mashed potatoes put into a tube and squeezed out into small circles, then coated with egg, rolled in breadcrumbs and then deep-fried. What is this dish called?

Croquettes?

Croquettes or duchesse. Maybe dauphine (which are cut with
chou paste).

Fritters, maybe. Croquettes, definitely. (Good call, jib71.)

Definitely croquettes. And they are delicious when one well!

Put some green onion in them and you have boxties. ^

Put some green onion in them and you have boxties. ^

A boxty (pl. boxties) is prepared with raw, grated potatoes, not mashed. See links:

http://en.wikipedia.org/wiki/Boxty

http://p208.ezboard.com/Boxties/fvernalalisasrecipeboardfrm136.showMessage?topicID =2083.topic

Ye definitley croquettes in the UK. Particularly good with gruyere and smoked bacon added!

Recipe Here (http://www.foodnetwork.com/food/recipes/recipe/0,,FOOD_9936_32311,00.html)

A boxty (pl. boxties) is prepared with raw, grated potatoes, not mashed. See links:

http://en.wikipedia.org/wiki/Boxty

http://p208.ezboard.com/Boxties/fvernalalisasrecipeboardfrm136.showMessage?topicID =2083.topic

I've had them both ways in and outside Ireland. Actually, I prefer the mashed ones. The grated ones are just a variation latkes to me.

I'm still leaning toward croquette. Check out this link, and see if it doesn't match OP's description:

http://en.wikipedia.org/wiki/Croquette