Prep the toppings. Pour each mix-in into its own shallow bowl or plate so you can roll the sandwiches easily.
Slice the donuts. Using a serrated knife, carefully cut each donut in half horizontally to create a top and bottom.
Add the ice cream. Place a scoop of ice cream on the bottom half of each donut. Gently press the top half down until the ice cream spreads to the edges.
Roll the edges. Roll the exposed ice cream rim in your chosen topping, pressing lightly so it sticks all the way around.
Serve straight away