- 3 pounds rinsed and hulled strawberries
- 1½ cups sugar
- 3 tablespoons strained fresh lemon juice
- Layer the strawberries and sugar in a large bowl. Cover and refrigerate overnight.
- Prepare for water-bath canning: Sterilize the jars and keep them hot in the canning pot, and put the flat lids in a heatproof bowl. (See below for details.)
- Using care not to damage the strawberries, gently transfer them with the sugar to a wide, 6- to 8-quart preserving pan. Bring to a simmer, gently stirring, then continue to cook for 5 minutes. Pour into a colander set over a large bowl. Return the juice to the pan and bring to a boil over high heat. Boil, stirring occasionally, until the syrup is reduced to 1 1/2 cups, about 15 minutes.
- Return the strawberries and any accumulated juice to the pan, along with the lemon juice, and bring to a simmer. Simmer, stirring frequently, until the strawberries are glossy and very tender but still hold their shape, about 20 minutes. Skim off as much foam as you can, then remove from the heat and stir gently for a few seconds to distribute the fruit in the liquid.
- Ladle boiling water from the canning pot into the bowl with the lids. Using a jar lifter, remove the sterilized jars from the canning pot, carefully pouring the water from each one back into the pot, and place them upright on a folded towel. Drain the water off the jar lids.
- Ladle the hot preserves into the jars, leaving ¼ inch headspace at the top. Use a damp paper towel to wipe the rims of the jars, then put a flat lid and ring on each jar, adjusting the ring so that it's just finger-tight. Return the jars to the water in the canning pot, making sure the water covers the jars by at least 1 inch. Bring to a boil, and boil for 5 minutes to process. Remove the jars to a folded towel and do not disturb for 12 hours. After 1 hour, check that the lids have sealed by pressing down on the center of each; if it can be pushed down, it hasn't sealed, and the jar should be refrigerated immediately. Label the sealed jars and store.