What they don't tell you in cookbooks about making jam and jelly may just be the one thing that actually gets you cooking it.
Drumroll, please: you only need all those sterilized glass jars if you are making a lot of jelly, with the intention and hope of enjoying it for over a month.
For me, knowing that I could whip up a small batch of fruit preserves without purchasing special equipment or hot sterilizing baths set me free. I was promptly off to the grocery to buy some Concord grapes (whose incredible flavor deserve their own ode-y blog post). What else did you buy, Marti? Oh, nothing. Because the only other things you need are some (okay, lots of) sugar and lemon juice.
I know, I know. Why doesn't everyone make their own jelly? I no longer have an answer.
Concord Grape Jelly*
1.5 lbs concord grapes
1.5 cups sugar
scant tbsp lemon juice
Chill 2 small plates (for testing jam).
Slip skins from grapes and purée skins with 1/3 cup sugar in a food processor, then transfer to a 4- to 6-quart wide heavy pot. Stir in lemon juice, peeled grapes, and remaining sugar and boil over moderate heat, stirring frequently and skimming foam, until pulp is broken down, about 20 minutes.
Force jam through food mill or sieve set over a large bowl. Discard remaining solids. Return jam to pot and cook at a slow boil, skimming foam occasionally and stirring frequently as mixture thickens to prevent scorching, about 25 minutes, then test for doneness.
To test jam, remove from heat, then drop a teaspoonful on a chilled plate and chill 1 minute. Tilt plate: Jam should remain in a mound and not run. If jam runs, continue cooking at a slow boil, testing every 5 minutes, until done, up to 15 minutes more.