In heavy medium sized saucepan or skillet, place 1/2 cup of sugar. Allow the sugar to carmelize over medium high heat while stirring constantly. After the sugar carmelizes (melts and turns golden brown), quickly pour hot "syrup" into 6 ramekins or custard cups. Set aside. Combine the remaining 1/2 cup of sugar in a medium sized mixing bowl with the eggs, egg whites, rice milk, Pumpkin Pie Spice and vanilla. Beat with an electric mixer until the sugar is dissolved. Add in the pumpkin and beat until smooth. Pour the mixture into the ramekins and place them in a shallow baking pan. Add hot water to the pan to a depth of 1 inch. Bake at 325 degrees for one hour or until a knife inserted near the center comes out clean. Remove cups from water and allow to cool. Cover ramekins with foil and refirgerate at least 2 hours before serving. To serve, slide a thin knife around edges of custard. Place a dessert plate upside down on the ramekin and invert it. Tap the bottom of the ramekin to shake the flan out onto the plate. Drizzle any remaining carmelized sugar over the top. To make you own pumpkin pie spice: Combine 1 1/4 tsp. of cinnamon, 1/2 tsp. o ground ginger, 3/8 tsp. of allspice and 3/8 tsp. of nutmeg.