Making Ghostbusters Stay Puft Marshmallows can be straightforward if you follow these simple steps:

1. Prepare Your Pan: Grease a rectangular baking dish and dust it with powdered sugar to prevent sticking.
2. Bloom the Gelatin: In a small bowl, combine gelatin and ½ cup of cold water. Let it sit while you prepare other ingredients.
3. Cook the Sugar Mixture: In a saucepan, mix granulated sugar, corn syrup, salt, and remaining ½ cup of cold water. Bring it to a boil over medium heat, stirring occasionally until dissolved.
4. Check the Temperature: Use a candy thermometer and cook the mixture until it reaches 240°F (115°C).
5. Combine Everything: Remove the sugar mixture from heat and add the bloomed gelatin. Stir until fully dissolved.
6. Whip the Mixture: Pour the mixture into a stand mixer. Beat on high for about 10 minutes, or until it becomes fluffy and triple in volume.
7. Color the Mixture: Gently fold in blue food coloring, ensuring it has the characteristic Stay Puft color.
8. Spread and Set: Pour the mixture into the prepared baking dish and smooth the top. Allow it to set for at least one hour until firm.
9. Cut the Marshmallows: Once set, dust your work surface with powdered sugar. Turn the marshmallow slab onto the surface and cut it into squares using a sharp knife.
10. Add Details: Use red food coloring to create Stay Puft’s iconic hat and tie on each marshmallow.