I know what you are thinking, whats so interesting about slicing onions. No I dont know why we cry or have a solution to prevent crying, when we slice onions. But according to an aunt of mine, slicing with a very sharp knife helps to prevent the tears.
What I want to show you is the two ways we cut onions. Well, in my house that is. In the old days there weren't any chopping boards, so most housewives sliced by holding the onion by hand and the knife in the other, even now my aunts still do this and so does my mother in law
The onion is sliced the normal way, from the side, and quite thinly.
For making local snacks and fish sambals ( mashuni) and salads the onion is sliced like this: ( see image below) and its best to slice as thinly as you possibly can.