* M&M's: This is the most common spelling, referring to the popular candy.
* Mmm: This spelling is used to represent a sound of pleasure or enjoyment, like when someone is eating something delicious.
* M.N.M.: This is a possible acronym or abbreviation. If you have more context, I might be able to help you figure out what it stands for.
Please provide more context so I can help you figure out the correct spelling!