Preheat Oven 350 degrees:
Cream the butter and cream in the sugar until fluffy. Separate the eggs, blend the beaten yolks into the butter mixture. Beat the egg whites and add to the butter mixture. Combine the milk with the vanilla and add to the butter mixture. Sift the flour with the baking powder and add to the butter mixture on low. Mix the batter until smooth and creamy.
Butter a bunt pan. Spoon brown sugar around the bottom, spoon your favorite jam over the brown sugar and finally spoon more brown sugar over the jam.
Spread the batter evenly over the jam and brown sugar mixture.
Bake about 35 minutes or until the toothpick test comes out clean.