1. Start by mixing the cake batter according to the instructions on the box. Once the batter is ready, divide it into three separate bowls. Tint one bowl red and one blue, leaving the third bowl white. This will create the vibrant tri-color effect in your cupcakes.

2. Preheat your oven and line a cupcake tin with paper liners. Carefully spoon small amounts of the red, white, and blue batters into each liner, creating a layered effect. This will result in a delightful surprise when the cupcakes are sliced open.

3. Bake the cupcakes according to the instructions on the cake mix box, typically around 18-20 minutes. Keep a close eye on them to ensure they don’t overbake. Once they’re golden brown and a toothpick inserted into the center comes out clean, remove the cupcakes from the oven and let them cool completely.

4. Using a sharp knife or a cupcake corer, gently remove the center of each cooled cupcake, creating a small well. Fill this well with your choice of small candies, such as mini M&Ms or Pop Rocks, to create a delightful burst of flavor when bitten into.

5. Be careful not to remove too much of the cupcake, as you want to ensure the tops stay firmly in place when you replace them. Gently press the tops back onto the cupcakes, securing the surprise filling inside.

6. Spread a generous amount of vanilla frosting over the tops of the cupcakes, ensuring a smooth and even coverage. Then, let your creativity shine by sprinkling a mix of red, white, and blue sprinkles over the frosted cupcakes.

7. To ensure your Firecracker Surprise Cupcakes stay fresh and delicious, store them in an airtight container at room temperature for up to 3 days. When ready to serve, arrange the cupcakes on a platter or individual plates, and consider pairing them with patriotic beverages like lemonade or iced tea for a complete summer celebration.