Gently separate the oreos by slowly twisting them apart. (Some will break, it's okay, just try to be gentle)
Separate the chocolate into 3 parts (this is to keep it from getting hard while you decorate) and place each section in a microwave safe bowl.
To make the chocolate easier to work with about 1/2 teaspoon vegetable oil to each section of chocolate (you can add more later if needed to thin it even more).
Melt in 20 second bursts in the microwave (Microwave 20 seconds, stir 20 seconds, etc.)
Be patient when melting and stir well in between bursts to avoid burning the chocolate.
Dip one end of the lollipop stick into the melted chocolate and press that side into the cream side of the oreo.
Place the other half of the oreo on top and gently press and hold.
Place the oreo on top of a fork over the bowl of melted chocolate. Use a spoon to spoon chocolate over the oreo.
Shake the fork gently on the edge of the bowl until the chocolate forms an even layer.
Place on a sheet of parchment paper.
Add M&M's in whatever pattern (using whatever colors) you like!
Press a miniature Reese's on the top of the oreo and hold to secure.
Allow to harden at room temperature.