Pre-heat oven to 350F, use a nonstick cookie sheet or line with parchment paper.
In a large mixing bowl, combine, butter, sugar, brown sugar, vanilla, and egg and mix well. Mix in flour, baking soda, and salt then fold in the chocolate chips.
Roll into Tablespoon sized balls and place on a nonstick pan.
Bake for 10 minutes or until cookies are set.
Remove from oven and quickly place valentine M&M’s onto the warm cookies. Transfer to a cooling rack.