8 cups raspberries, blackberries, boysenberries, blueberries or hulled strawberries
About 1 1/4 cups sugar
3 tablespoons lemon juice
Rinse the berries, drain until dry and put in a 10-by-15-inch baking pan. If using strawberries, slice them. Mix fruit with the sugar to taste and the lemon juice. Bake, uncovered, in a 375-degree oven until berries release juice, for about 10 minutes. Meanwhile, put a ceramic saucer in freezer.
Reduce oven temperature to 325 F. Every 20 minutes or so, gently stir berries to moisten well with juices. Bake until a little berry liquid, spooned onto chilled saucer, doesn't immediately flow together when you pull tip of a spoon or your fingertip through it (as you lift your finger, liquid holds on, forming a small droplet), about 1 hour for blueberries, 1 to 1ï»¿1/2 hours for other berries.
Let jam cool; if necessary, reheat and adjust consistency (see following directions).
Spoon into a bowl or small jars. Serve or cover airtight and chill for up to 2 weeks; freeze to store longer, up to 12 months. Makes about 1 1/2 cups raspberry, blackberry, boysenberry or strawberry jam, about 2 1/2 cups blueberry jam.
To adjust jam consistency, let jam cool completely in baking pan. If too runny, return to oven, stir and test every 20 minutes until jam reaches desired thickness. If jam is too thick, warm it in oven, then stir in water, 1 teaspoon at a time, until it is desired consistency.
— Recipe from Sunset Magazine's July 1994 issue.