**Prepare the Cake**

Follow the instructions on the box to prepare the cake mix, incorporating the canola oil if applicable. Bake the cake and allow it to cool in the pan for 15 minutes. Carefully run a thin knife around the tin’s edge to release, then invert into a large bowl. Break the cake apart by hand into fine crumbs and leave to cool fully.

**Make the Frosting**

In a mixing bowl, combine softened butter, icing sugar, vanilla, and milk. Beat on medium speed for 4 minutes using a hand or stand mixer fitted with a paddle attachment, until the mixture is light and airy.

**Combine and Form Cake Balls**

Add three-quarters of the frosting to the crumbled cake. Mix gently until just incorporated. Test the texture – if it's firm enough to roll, do not add more frosting; otherwise, incorporate the remainder. Take tablespoon portions and roll into smooth balls, placing them on a lined tray. Chill in the freezer for 10 minutes or refrigerate for 30 minutes. Roll each ball again for a smoother finish and chill once more – 30 minutes in the freezer or 1 hour 30 minutes in the refrigerator.

**Dip and Decorate**

Melt half the chocolate in a microwave-safe mug using 20-second bursts, stirring in between, or melt via a double boiler. Transfer to a deep cup. Dip the end of a cake pop stick into the chocolate and insert halfway into a cake ball. Repeat for all.

Dip each pop into the melted chocolate, ensuring full coverage. Gently tap off the excess and swirl to finish. Decorate promptly with sprinkles before the coating sets. Stand upright in a stable holder such as styrofoam or a box with holes.

**Repeat and Finish**

Continue with remaining cake pops. Monitor the chocolate's consistency – reheat as needed – and maintain the cold temperature of the cake balls. If they begin to soften, briefly return them to the freezer or fridge.

Let all cake pops set completely before serving.