expression
leave it to me; count on me
Kansai dialect contraction of 任せておきなさい or similar, used to reassure someone that you'll handle something. Casual and friendly.
See also: とき
「この仕事、誰がやる？」「まかしとき！」
"Who's going to do this job?" "Leave it to me!"
心配せんでもええよ、まかしとき。
Don't worry, I've got this.