Prepare the cake as package directs and add vanilla.

Bake it in a 9x13 pan lined with nonstick foil for 15-20 minutes at 350.

Electric mix butter, flour, sugar and cinnamon to make crumbs.

After the 15-20 mins, carefully spread the jam across the top. (dollop and use an offset spatula and tread carefully)

Sprinkle crumbs all over the cake and return to the oven for an additional 20-25 minutes.

Let cool completely before cutting.