What is NOT a step in the procedure for making a chiffon pie filling that contains gelatin?

Folding whipped cream into the warm base is not a step in the procedure for making a chiffon pie filling that contains gelatin. In chiffon pie preparation, it is essential to first allow the base mixture, which has been heated, to cool slightly before incorporating whipped cream. This is crucial because if the whipped cream is added while the base is still too warm, it can melt and lose its volume, leading to a filling that lacks the light and airy texture characteristic of a chiffon pie.

On the other hand, the other steps, such as heating the base, softening the gelatin, and chilling the filling, are integral to creating a proper chiffon pie. Heating the base helps dissolve the gelatin properly and allows flavors to meld, while softening the gelatin ensures it activates correctly during the mixing process. Chilling the filling is essential as it sets the pie, allowing it to achieve the right firmness and texture when served.