Using a food processor to make Oreo truffles creates the best filling because it finely grinds the Oreo cookies to create a smoother texture. A blender will also work. If you do not have either of these pieces of equipment, don’t fret! Place your cookies in a plastic bag and crush the cookies with a rolling pin. Then mix together with a stand mixer, hand mixer, or the good old fashioned way with a wooden spoon and large bowl.