Melt the chocolate chips in a microwave-safe bowl in a microwave set on medium for 2 minutes. Stir halfway through the heating time. Melt thoroughly, but be careful not to overheat. Gently mix the Rice Krispies into the chocolate and pour into a greased 9x12-inch pan. Slam the pan on the counter or floor to level the chocolate. Refrigerate until firm, about 30 minutes. Cut the candy in half widthwise and then cut it twice lengthwise, making 6 bars.