I have never seen a recipe for puffed rice, and this one is sketchy on the information at best. You will also notice that it doesn’t mention rice or puffed rice in the ingredients. The closest recipe I could find in my research was for a puffed rice candy from 1920. Based on similar ingredients, I am going to assume this is for puffed rice candy, and I will add the instructions to make that treat. My additions will be in italics.

To Make Puffed Rice (Elda Hartman)

6 c puffed rice

1 cup of sugar

3/4 cup of water

1 tablespoon full of butter

2 tablespoons molasses

1 tablespoon vinegar

a little salt

Toast rice until crispy at 350 on a cookie sheet then set aside. In a pan mix sugar, water and vinegar and bring to a boil for 5 minutes. Remove from heat and add butter and molasses. Return to heat and bring back to a boil. Boil until mixture reaches hard ball (turns crispy in water). Mix in toasted puffed rice and stir until all coated. Press into a flat pan then press down on the rice to flatten it and cut into squares while still hot.