This is an Egyptian slang in response to the Arabic greeting "As-salamu alaykum/Peace be upon you".
It is formed by quick pronunciation of the classic response "Alaykum as-salam wa rahmatolaah wa barakato".
A- = Alaykum
-ssa- = As-salam
-ra- = rahmatollah
-kato = barakato

عسراكاتو