In a mixing bowl, combine the crushed biscuits, cocoa powder, and melted butter. Stir until it forms a crumbly mixture.

Incorporate the sweetened condensed milk into the biscuit mixture. Mix until combined and then firmly press this mixture into a lined rectangular dish to form the base.

In a separate bowl, take the shredded coconut and divide it into six smaller bowls. Add a few drops of different food colorings to each bowl, mixing until the coconut is brightly colored.

Gently sprinkle the colored coconut over the base, creating a rainbow effect. Start with red, then orange, yellow, green, blue, and finally purple. Press each layer down gently to keep them intact.

Place the dish in the refrigerator to chill for at least two hours or until set.

Once set, top with mini marshmallows for an added layer of fun!

After chilling, slice it into squares or rectangles and serve.