Step 1

In a mixing bowl, whisk together the sugar, cocoa powder, and salt until combined. Set aside.

Step 2

Fill a medium pot almost halfway with water. Bring the water to a simmer over low heat.

Step 3

Place a heat-safe bowl (glass or stainless steel) that can just fit on top of the pot of simmering water, but leaves a gap between the water and bottom of the bowl.

Step 4

Add the white chocolate chips to the bowl. Keep the heat on low and use a rubber spatula to stir the melting chocolate chips until smooth. Once smooth, add cinnamon and stir to combine. Remove the bowl of chocolate, but leave the water in the pot to be used later.

Step 5

Add a heaping spoonful of the melted chocolate to each of the six chocolate molds. Use the spoon to spread the chocolate up the sides of each mold. Make sure the entire inside of each mold is evenly coated with chocolate. (Save extra chocolate to use later.)

Step 6

Freeze the chocolate for 10 minutes, or until completely set.

Step 7

Line a baking sheet with parchment paper.

Step 8

Once set, carefully remove the chocolate cups from the mold, placing them on the lined baking sheet.

Step 9

Flip over three of the molds to be filled. Fill each of the three halves with 2 tablespoons of the hot cocoa mix, ½ teaspoon cinnamon, and 5-6 mini marshmallows.

Step 10

Place the other three halves, seam-side down, on a separate baking sheet. Place the sheet on top of the pot of warm water over low heat to slightly melt the rims of the molds.

Step 11

With gloves on (so you don't leave fingerprints) cover each filled chocolate half with an empty half, sealing it.

Step 12

Decorate with any extra melted chocolate, remaining cinnamon, sprinkles, and other cookies and candies. Use immediately, or within 24 hours, for best results. Store at room temperature.

Step 13

To make hot chocolate, add a snickerdoodle bomb into a mug. Slowly pour about 1½ cups of hot milk over the bombs and stir. Sip and enjoy!