When working with fresh produce, a less-is-more approach usually produces better results than trying to follow a complicated recipe. And what could be simpler than making jam with berries, sugar, and lemon juice?
[I have to put in a warning here. This was my first time making jam, and having 16 pounds of strawberries to use up, I decided it would be better to make all the jam at once. It didn't hit me until my jam was merrily boiling away at the half-hour mark that the smaller surface-area-to-volume ratio of my giant batch would make my jam much, much runnier than it should have been. Luckily, my jam came out okay (a little on the runny side), but making larger batches than a recipe recommends is a big no-no when it comes to jam making.]
3 lb. ripe strawberries (4 1/2 pints), rinsed and hulled
3 cups sugar (you can use a little less if the fruit is very ripe)
Juice of 1/2 a lemon
Special equipment: eight or nine 8-oz canning jars with lids
To wash the berries, gently scoop them into a sink filled with water. Swish them around a little, and let them sit for a while. The dirt should fall to the bottom of the sink.
Hull and quarter the berries. Put them in a deep pot made of non-reactive material (stainless steel works well). Make sure that there is enough room in your pot! If there is less than 5" between your berries and the top of your pot, you might have a rather anxious time of it. When the jam boils, lots of air bubbles are trapped in the dense liquid, which will begin to rise very quickly.
Pour on the sugar and lemon juice, and mix well with a wooden spoon. Cover the pot and let the berries macerate for about two hours. If you like your jam smoother, you can mash them with a potato masher instead.
While the berries macerate, wash your jars and set them in the oven. They should be in there for at least half an hour. Wash the lids and rings, and set the rings aside. Put the lids in a pot of boiling water to sterilize them, and to make the rubber around the edges a little more pliable.
Bring the pot of strawberries to a full boil (you need to boil off the liquid to achieve a jammy consistency). Make sure to stir often (with your wooden spoon) and skim off any foam from the surface. The foam will make your jam cloudy if it's left in the pot, although you can eat it separately (a la Marcel from Top Chef). After half an hour of boiling, your jam should be just about ready. Don't boil the jam for more than 40 minutes, however, otherwise the pectin in the fruit will break down and the jam will turn dark.
You can test the consistency of the jam by chilling a plate in your freezer. Spoon a little bit of jam onto the plate, and check the thickness of the jam once it has cooled. I've found that the jam tends to thicken up a little more than this test might indicate once you've sealed and refrigerated the jars though, so don't think it's the end of the world if your jam is a little runny.
Take a jar out of the oven and ladle the jam in until within 1/4" of the rim. Wipe any jam off the rim with a damp towel, and use tongs to take a lid out of your pot of boiling water and put it on the jar. Quickly screw a ring over the lid (it has to be tight enough to hold the lid onto the jar). Repeat this process until you fill up all of your jars.
Put the jars into a deep pot filled with boiling water; make sure the water reaches above the rim of the jar lids. Cover, and let the jars boil for ten minutes. Remove the jars with tongs and let them cool on the counter. The lids should begin to pop within minutes. If you have any lids that didn't seal (the lid makes popping sounds when you press down on the middle), throw them out or eat immediately.
This jam will keep in a cool, dark place for one to two years. If you haven't already eaten it by then. We can go through a jar of this stuff in a day!
Inspired by this recipe from Gourmet, 1999.