To make the crust, in a medium bowl, combine the baking mix, 1/4 cup sugar, melted butter and milk. Stir until a dough forms, then turn the dough out onto a clean surface that has been dusted with some baking mix. Knead for 30 turns. Pat the dough into the bottom and up the sides of an ungreased 9 inch round cake pan. In the same bowl, beat together the remaining 1/2 cup sugar, vanilla, eggs and cream cheese. Pour over the dough in the pan.
Bake for 30 minutes in the preheated oven, until the edges are golden and the filling is set. Allow the coffee cake to cool for 10 minutes, then spread the fruit preserves over the top.
