In a medium saucepan place chopped pears, 1/4 cup water, sugar, and dried sage, if using. Cook and stir over medium-low heat until bubbly. Boil gently, uncovered, for 20 to 25 minutes or until mixture is very thick and liquid is nearly evaporated, mashing fruit lightly after 15 minutes of cooking. Adjust heat to maintain a gentle boil. (If using canned pears, drain pears, reserving 1/4 cup of the liquid. Finely chop canned pear halves. Cook as above using reserved liquid in place of water.)
Remove from heat. Stir in fresh sage, if using. Cool completely. Makes about 1 cup.