a piece of cake

[At a cram school]

Wow you don't look nervous at all the day before Eiken!

　Nope as I have been studying for this test ALL MY LIFE!!!!

　It is going to be a piece of cake!

Good luck!

[塾にて]

英検試験前日なのに、落ち着いてるね〜！

　んん。このテストに自分の人生をかけてきたからね！

　明日は朝飯前だよ！

頑張って！