Step 1: In a microwave-safe bowl, combine the gelatin powder and 1/2 cup of water. Stir well.
Step 2: Microwave the mixture on high for about 1 minute. Remove and stir until the gelatin is completely dissolved and the liquid is clear.
Step 3: Add the mini marshmallows to the hot gelatin mixture. Microwave for another 30-45 seconds, just until the marshmallows are puffy.
Step 4: Whisk the mixture gently until the marshmallows are melted and smooth. The mixture will have a clear bottom and a frothy white top.
Step 5: Pour the mixture into an 8x8 or 9x9 inch square glass pan. Do not grease the pan unless it is prone to sticking.
Step 6: Refrigerate the pan for 45 to 60 minutes, or until the gelatin is set but still flexible.
Step 7: Use a knife to loosen the edges of the jello from the pan. Carefully peel the jello sheet up and roll it tightly into a log.
Step 8: Slice the log into 1-inch pieces using a sharp knife or clean dental floss to reveal the spiral pattern.