When the gelatin is soft, heat the saucepan over low heat, stirring, until the gelatin is dissolved and incorporated into the vodka mixture, about 10 minutes. Remove the pan from the heat.

A recipe for classic strawberry jam in “Better Homes and Gardens Jams & Jellies” (Houghton Mifflin Harcourt, $19.99) calls for 7 cups of sugar to 12 cups of strawberries and a 1.75-ounce ...