In a large, heavy-bottomed pot, combine chopped peaches and lemon juice. Stir well to combine.
Place the pot over medium heat and cook for 2 to 3 minutes. Add now sugar and stir thoroughly.
Bring the mixture to a boil, stirring frequently to prevent sticking. Once it boils, reduce the heat to low and let it simmer, uncovered, for about 30 minutes. Stir occasionally to prevent burning. The jam is ready when slightly thick and creamy.
After cooking, you can blend the mixture to get a creamier jam. Or leave some fruit pieces in, if you desire more texture.
Once it reaches the desired consistency, remove the peach jam from the heat and transfer into clean, sterilized jars while it is still hot.