こんにちわ！

お肉やハムの場合、"一切れ" "二切れ"と言います。

難しいのは数の発音で、通常と違います。

You can say "hito kire" " futa kire" in case of the meat, ham, and anything like that.

The difficulty is pronouciation of numbers  is different from usual.

Please check it in dictionary or google :)　

Hi,
You can say 一切れ(ひときれ), 二切れ(ふたきれ), and 三切れ(みきれ).
Another possible counter suffix is 枚(まい): 一枚(いちまい), 二枚(にまい), and 三枚(さんまい).
A very thin sliced ham in a sandwich, for example, can be an example of 1枚のハム.

Hope it helps.