Cake

cakewalk

Meaning: something that can be easily accomplished.

Example: I thought the course was going to be difficult, but it ended up being a cakewalk. Read on

icing on the cake

Meaning: when something good is added to another good thing that you already have

Example: Everyone expected him to do well in the exams. Getting first rank was the icing on the cake. Read on

sell like hot cakes

Meaning: be a great commercial success

Example: These books are selling like hotcakes. Read on

a piece of cake

Meaning: very easy task

Example: Don't worry, Sophie - this job interview will be a piece of cake for you - you have all the skills they need and I think you're absolutely the best candidate. Read on