(do something) with one hand tied behind (your) back

to do something very easily.

Cleaning your bike chain is so simple a chimp could do it with one hand tied behind its back.

• have butterflies in your stomach
• have by the balls
• have by the short and curlies
• have cake and eat it
• have cake and eat it too
• have carte blanche
• have clean hands
• have come a long way
• have coming out ears
• have coming out of ears
• have coming out of your ears
• have coming out your ears
• have day in court
• have dead to rights
• have designs on
• have designs on someone
• have designs on something
• have dibs on
• have dibs on something
• have done more something than has had hot dinners
• have done more something than someone has had hot dinners
• have done more than has had hot dinners
• have done more than someone has had hot dinners
• have [done/seen/had etc.] more something than has had hot dinners
• have [done/seen/had etc.] more something than someone has had hot dinners