In a 9- by 13-inch cake pan, bake the cake as directed on the box. Let cool completely.
Once the cake is baked, get organized and set aside plenty of time (a few hours) to crumble, roll, shape, dip, and decorate 4 dozen cupcake pops.
Crumble the cooled cake into a large mixing bowl. The texture of the cake causes it to crumble easily. To make crumbling easier, first cut the baked 9- by 13-inch cake into 4 equal sections. Remove a section from the pan, break it in half, and rub the two pieces together over a large bowl, making sure to crumble any large pieces that fall off. You can also use a fork to break any larger pieces of cake apart. Repeat with each section until the entire cake is crumbled into a fine texture. If you have large pieces mixed in, the cake balls may turn out lumpy and bumpy. You should not see any large pieces of cake.
Add three-quarters of the container of frosting. (You will not need the remaining frosting.) Mix it into the crumbled cake, using the back of a large spoon, until thoroughly combined. If you use the entire container, the cake balls will be too moist.
The mixture should be moist enough to roll into 1 1/2-inch balls and still hold a round shape. After rolling the cake balls by hand, place them on a wax paper–covered baking sheet.
Cover with plastic wrap and chill for several hours in the refrigerator, or place in the freezer for about 15 minutes. You want the balls to be firm but not frozen.
Remove the baking sheet from the refrigerator or freezer and begin shaping the cake balls into cupcakes. Take a chilled ball and roll it into a cylinder shape. Then slide it into the flower-shaped cookie cutter. The cake mixture should fill the entire cutter, with any excess forming a mounded cupcake top on one side. You can use your thumb to keep the shape flat on one side, allowing the rest to form a mound on the other. When you have the shape the way you like it, gently push the shaped cupcake out of the cutter from the bottom. If the mixture is still firm enough, you should also be able to gently pull it out by holding the top mounded side.
Place the cupcake-shaped cake ball, right-side up, back on the wax paper–covered baking sheet. Continue with the remaining cake balls.
Once the balls are all shaped into cupcakes, return them to the freezer for 5 to 10 minutes to keep them firm.
Place the chocolate candy coating in a deep, microwave-safe plastic bowl. These bowls make it easier to dip the cupcake bottoms completely in candy coating while holding the bowl without burning your fingers. (It is usually easier to work with about 16 ounces of coating at a time.)
Melt the chocolate candy coating, following the instructions on the package. Microwave on medium power for 30 seconds at a time, stirring with a spoon in between. You can also use a double boiler. Either way, make sure you do not overheat the coating.
Take a few cupcake-shaped cake balls at a time out of the freezer to work with. Transfer the rest to the refrigerator at this point, so they stay firm but do not freeze.
One at a time, take a cupcake-shaped cake ball and, holding it by the mounded top, dip the bottom into the melted chocolate candy coating — just to the point where the mounded shape starts. Remove it from the chocolate, turn it upside down, and swirl your hand in a circular motion. This will cause any excess chocolate coating to slide down. When the coating reaches the bottom of the mounded cupcake top shape, you can stop. Have a dish towel handy to wipe off your fingertips, as it is highly likely that you will get some coating on them. Don't use water to rinse your hands, as getting water in the coating can make it unusable.
Place the half-coated cupcake shape on the second wax paper–covered baking sheet, chocolate-candy-coating-side up, mounded side down. Immediately dip about 1/2 inch of the tip of a lollipop stick into the melted candy coating, and insert the stick straight into the flat, chocolate-coated bottom of the cupcake while the chocolate is still wet. Push it no more than halfway through. Continue with the rest of the cupcake-shaped cake balls. Allow the chocolate to dry completely.
Melt the pink candy coating in the same way as the chocolate.
Holding its lollipop stick, dip the top of a cupcake in the melted pink candy coating. It should completely cover the rest of the exposed cupcake and meet the edge of the chocolate coating.
Remove the cupcake pop from the coating and turn it right-side up. If the coating is too hot, it will start to drip down the sides. If this happens, let the coating sit for a few minutes to cool and start to thicken. Then when you dip the tops, the coating will stay in place.
While the coating is still wet, use a toothpick to touch up any areas the coating may not have covered. Then place 1 M&M (M-side down) on the top and add sprinkles for decoration.
Place the cupcake pop in a prepared Styrofoam block to dry completely. Repeat with the remaining cupcake pops.
Store the cupcake pops in an airtight container on the counter or in the refrigerator for several days. You can also cover them in small treat bags, tied with a ribbon, and leave them in the Styrofoam block on the counter.