1 3/4 cups water
3 1/2 cups white sugar
1 1/2 cups vegetable oil
1/3 cup distilled white vinegar
1 teaspoon lemon zest
4 eggs
1 teaspoon vanilla extract
1 cup chopped pecans
Preheat the oven to 350 degrees F (175 degrees C). Grease and flour a 9x13 inch pan.
In a large saucepan, combine the water, sugar, oil, vinegar and lemon zest. Bring mixture to a boil and pour over cake. Pour over cake while still warm.
Bake in the preheated oven for 35 to 40 minutes, or until a toothpick inserted into the center of the cake comes out clean. Let cool in pan for 10 minutes, then turn out onto a wire rack and cool completely. Cool completely.
In a medium bowl, beat egg yolks until frothy. Add 1/2 the orange juice, 1/2 the blueberry juice, lemon juice and pecans. Mix gently until well blended. Beat in lemon frosting, then drizzle over cake.