INGREDIENTS
To prepare fruit. Sort and wash fully ripe strawberries; remove stems and caps. Crush berries.
To make jam. Measure crushed strawberries into a kettle. Add pectin and stir well. Place on high heat and, stirring constantly, bring quickly to a full boil with bubbles over the entire surface. Add sugar, continue stirring, and heat again to a full bubbling boil. Boil hard for 1 minute, stirring constantly. Remove from heat; skim.
From USDA #56