Melt butter and chocolate together in a saucepan on low.
Remove from heat and stir in sugar, 1/3 cup of jam, vanilla and eggs.
Add flour and baking powder and combine well.
Divide among sprayed jars and add 1 tsp jam to the top of each jar.
Cover each jar with aluminum foil and place in a slow cooker.
Pour enough water in the slow cooker that it hits about half way up the jars (Do not overfill or water will boil over into your brownies).
Cover and cook on high for 3 hours or until an inserted toothpick comes out clean.
Serve warm in jars with fresh raspberries and whipped cream or cool for 10 minutes and then carefully remove from jars and cool completely before slicing.