Begin by washing your ripe peaches thoroughly under cool running water. Halve them, remove the pits, and chop the flesh into bite-sized pieces. If you prefer a smoother texture, blanch the peaches in boiling water for about 30 seconds to make peeling easier.

In a large pot, combine the chopped peaches, sugar, and lemon juice. Mix until the sugar begins to dissolve and the juices from the peaches start to flow — this should take about 5 minutes.

Place the pot on the stove over medium heat and bring the peach mixture to a gentle boil, stirring frequently. You'll know it’s ready to simmer when small bubbles form around the edges, usually in about 10 minutes.

Reduce the heat to low and let the peach mixture simmer for 20-30 minutes, stirring occasionally. It's done when it coats the back of a spoon.

While your peach jam simmers, preheat your oven to 200°F (93°C). Place clean canning jars on a baking tray and sterilize them for about 10 minutes.

Once the peach jam has reached its desired thickness, carefully ladle it into the sterilized jars, leaving about 1/4 inch of headspace at the top.

Place the sterilized lids on the filled jars and tighten them slightly. Let the jars cool to room temperature, usually around an hour.