cake walk

Short definition from Wiktionary

Noun

1. 1
   A type of dance originating in the United States in the 19th century.
2. 2
   From the mid 1900s, a game at a fair or party in which people walk around a numbered circle along to music. When the music is stopped, the caller draws a number from a jar and whoever is standing on or closest to that number wins a cake.
3. 3
   Something extremely easy.
4. 4
   Alternative spelling of cake walk.