Wash peaches. Peaches are easily peeled by dipping in boiling water for 1 minutes, then in cold water. To prepare pulp, remove pits from peeled peaches, then chop. Cook until soft, adding only enough water to prevent sticking (about 1/2 cup). Press through a sieve, food mill, blender or food processor.
Weigh or measure the pulp. For each pound or measure of pulp, add 1/2 pound or 1/2 measure of brown sugar. (Or use 4 to 4 1/2 pounds of peaches to 4 cups sugar). Some feel the taste is improved by adding the juice of a half lemon to 2 quarts of pulp.
To make butter: add sugar to peaches in a large pot and cook until thick over low heat for about 30 minutes as mixture thickens, stirring frequently to prevent sticking.
Pour hot peach butter into hot canning jars, leaving 1/4-inch head space. Wipe jar rims and adjust lids. Process for 10 minutes in a boiling water bath.
Variation: Spiced Peach Butter: Follow recipe for Peach Butter. Add 1/2 to 1 teaspoon of ground ginger and 1/4 teaspoon nutmeg with sugar to the peach pulp during the final 10 minutes of cooking. Process for 10 minutes in a boiling water bath.