Mix all topping ingredients together and place in refrigerator for 10 to 20 min. to harden. Meanwhile, in a bowl, mix the flour, sugar, baking soda and spice. Next, in a separate bowl, combine the eggs, orange juice, molasses, oil and sour cream. Stir the wet ingredients into the dry until just combined. Pour into a greased 8- or 9-inch round baking pan. Next, pinch small amounts of the topping onto to the top of the batter. Distribute evenly, leaving gaps between topping so the craters can form during baking. Bake at 375 degrees for 25 to 30 min. or until a toothpick comes out clean (from the cake, not the topping). Let cool in the pan on a wire rack.
Cut and serve warm with coffee.