Soak 2 envelopes Knox gelatin in 1/2 cup cold water. Heat 4 cups whole milk, hot, not boiling. Remove from heat; add 2 cups sugar (more if desired), 2 teaspoon vanilla, and 1 teaspoon salt. Put in ice box or cold place for 5-6 hours before freezing. Makes 1 gallon. Ingredients can be suited to taste.