Preheat the oven to 350 degrees F. Lightly coat a 10-inch Bundt pan with a thin film of vegetable spray and wipe the excess with a paper towel. To prevent the cake from sticking, cut 2 or 3 strips of waxed or parchment paper 1-1/2 x 5 inches and press them into the bottom of the pan, overlapping the ends to make a circle. Spray the paper lightly and set aside the pan.

Measure the flour, then sift it into a medium-size bowl with the baking powder, baking soda, salt, cinnamon, cloves, allspice, ginger and nutmeg. Blend the mixture well and set it aside.

In a large bowl beat the oil, vanilla sugar, brown sugar and 1 teaspoon orange zest with an electric mixer (not a food processor) on high speed about 2 minutes or until thick and thoroughly blended. Add the egg substitute, 1/4 cup at a time, beating after each addition just until it is incorporated into the batter. Add the vanilla and continue beating for 4 to 5 minutes or until the batter is light and frothy.

Sprinkle 1/3 of the flour mixture over the batter and, on low speed, beat it in thoroughly, but stop as soon as the flour is incorporated. With each of the following additions beat gently, thoroughly but quickly and don't overbeat or the texture of the cake will suffer. Scrape the sides of the bowl and add 1/2 cup of the buttermilk. Beat on low speed just until it is absorbed, add half the remaining flour and beat it in quickly. Keep the speed low at all times. Add the cognac and remaining 1/4 cup buttermilk, beat again, and then incorporate the remaining flour.

Pour the batter into the prepared pan and bake for 35 to 40 minutes or until a toothpick or long-fined fork inserted in the center comes out dry. Set the cake aside for 8 to 10 minutes before unmolding it.

For the topping, combine the ingredients (1/4 cup low-fat buttermilk, 1/4 cup vanilla sugar or granulated sugar, 1/4 tsp baking soda,1/4 tsp vanilla extract, 1 tsp grated orange zest) in a small bowl and stir until they are thoroughly mixed. Run a knife between the cake and the pan to loosen it. Place a cake platter over the cake and (using potholders to protect your hands) turn the cake and platter upside down in one swift motion and set it on the counter. Slide the pan up and off the cake. While the cake is still hot, use a skewer or toothpick to poke small holes in several rows 2 inches apart about halfway down into the cake (so the cake will absorb the topping). Pour the topping over the top of the cake, spreading it evenly. Some of it will drip down the sides. Set aside to cool before serving.