Here's the recipe:
1 20 ounce can unsweetened crushed pineapple
1 stick plus 3 tablespoons unsalted butter, softened
3 1/2 cups packed light brown sugar
1/2 cup dark rum
3 1/3 cups flour
1 1/2 teaspoons baking powder
1 teaspoon baking soda
- preheat oven to 325. Wash 8 (1 pint) wide mouth canning jars with lids in hot, soapy water and let them drain, dry and cool to room temperature. Grease insides of jars.
- Drain crushed pineapple for about 10 minutes in a colander, reserving juice. Puree drained pineapple in food processor or blender. Measure out 1 1/2 cups puree, adding a little juice if necessary to make 1 1/2 cups. Set puree aside. Discard remaining juice.
- With mixer, beat butter and half of brown sugar until light and fluffy. Beat in eggs, then remaining sugar. Beat in pineapple puree and rum. Set aside.
- Sift together flour, baking powder and baking soda. Gradually add to pineapple mixture in thirds, beating well after each addition to make a thick batter.
- Spoon 1 level cupful of batter into each jar. Carefully wipe rims clean. Place in center of preheated oven. Bake 40 minutes.
- About 10 minutes before cakes are done, bring a medium saucepan of water to a boil. Put in jar lids, cover and remove from heat. Keep lids in hot water until they are used.
- When cakes are done, remove jars from oven. (I like to tip an extra tablespoon of rum in each jar before sealing). If jar rims need cleaning, use moistened paper towel. Put lids and rings on in place, then screw tops tightly shut. Place jars on a wire rack and they will seal as they cool.