An M&M birthday cake will work well for both a child's party as well as a party with a specific colour scheme, as that colour scheme can be reflected in the colour of the M&M cake. The M&M characters have become well known through print and television advertising campaigns, making the cake characters widely recognisable by adults and children alike. The cake character is relatively simple to make in that you can use a basic, round cake pan. The size of the cake will vary depending on the size of the party.
Bake a cake in a round cake pan following the recipe instructions. Allow to cool completely.
Select a M&M character to recreate. The commonly seen ones in M&M advertising are green, red and yellow. The green M&M is female while the red and yellow are typically male.
Mix vanilla frosting with either red, yellow or green food colouring, depending on the character you are recreating. Frost the entire cake with this icing.
Form a lower case "m" in the bottom centre of the cake using white M&M candies. These may need to be special ordered from the M&M official website, as white is not included in a traditional M&M candy bag, although there are colour exceptions around holidays.
Form eyes, eyebrows and a mouth using white M&M candies for the whites of the eyes and brown M&M candies for everything else. If you are creating the female green M&M use the brown M&M candies for eyelashes as well. The brown M&M candies can be found in a traditional M&M bag.
Fill in the remaining area of the M&M by placing M&M candies of the same colour of the frosting onto the cake. The frosting is in place to fill in the gaps between the candies so only the selected colour shows through.