4 pears, peeled, cored and cut into 1" pieces
1/2 pineapple, peeled, cored and cut up
4 cups sugar
1/3 cup fresh lemon juice
grind up pineapple in food processor (this is where it's obvious that if you have canned crushed pineapple in the cupboard, you could cheat, but I recommend fresh pineapple)
strain juice into a saucepan. reserve pineapple. add pears to juice and bring to simmer over medium-low heat. simmer about 10 minutes, until pears are soft.
add pineapple, sugar and lemon juice. bring to a simmer. reduce to low heat and simmer for about an hour. (you want the jam to fall chunky-like) from the spoon.
ladle into hot jars and process 10 minutes in water bath or steamer.