Place the chocolate chips, nuts, or sprinkles on a small plate. Line a plate or sheet pan with waxed paper.
Using a small (1 tablespoon or ½ ounce) ice cream scoop, place a scoop of ice cream on the flat side of a cookie. Top with another cookie, placing the flat side on the ice cream. Press together gently. Roll the edges in chocolate chips, nuts, or sprinkles and place on the prepared plate. Repeat with remaining ingredients. Place the sliders in the freezer for at least 1 hour before serving.