My grandmother made strawberry jam every June without fail. She didn't use pectin. She didn't use a thermometer. She used strawberries, sugar, lemon juice, and a lifetime of knowing exactly when it was done.

I've been making this recipe for fifteen years now, and I still think of her every single time.

What you'll need

• 4 cups fresh strawberries, hulled and roughly chopped
• 2 cups granulated sugar
• 2 tablespoons fresh lemon juice
• A wide, heavy-bottomed pot
• Clean jars with lids

The method

Combine the strawberries and sugar in your pot and let them sit for 30 minutes to an hour. This draws out the juice and starts the process before you even turn on the heat. Don't skip this step — it makes a difference.

Add the lemon juice and bring the mixture to a boil over medium-high heat, stirring frequently. Once it's boiling, reduce to a steady simmer and cook for 20 to 30 minutes, stirring often and skimming any foam that rises to the top.

How to know when it's done

The old-fashioned test: put a small plate in the freezer before you start. When you think the jam might be ready, drop a small spoonful onto the cold plate and wait 30 seconds. Push it with your finger — if it wrinkles and holds its shape, it's done. If it's still liquid, keep cooking.

The jam will also look noticeably thicker and darker, and the bubbles will change from large and frothy to smaller and more syrupy.

Storing your jam

For refrigerator jam (which I usually make), simply ladle into clean jars, let cool to room temperature, and refrigerate. It keeps for 3 to 4 weeks.

For shelf-stable jam, process in a water bath canner for 10 minutes. Properly sealed jars will keep for up to a year in a cool, dark place.

A note on strawberries

Use the best strawberries you can find. Farmers market berries in June are incomparably better than grocery store berries in January. The jam is only as good as the fruit you start with. If you can pick your own, even better.

This recipe makes about 3 half-pint jars. I always make a double batch — one to keep, one to give away. There is no better gift than a jar of homemade jam.