Preheat the oven to 350 degrees F (175 degrees C). Grease and flour one 9x13 inch baking pan.
In a large bowl, cream butter and 1 1/2 cups sugar until light and fluffy. Beat in baking powder, baking soda, and salt. Add eggs and mix well.
Stir in sour cream and vanilla. Gradually add flour to the creamed mixture, mixing until all of the flour is absorbed. Stir in walnuts, raisins, cranberries, and apricot preserves.
Spoon batter into prepared pan.
Bake at 350 degrees F (175 degrees C) for 30 minutes or until a toothpick inserted into the center of the cake comes out clean.
Cool cake in a pan on a wire rack.
To Make Frosting: In a medium saucepan, heat 1/4 cup sugar and 1/3 cup water over medium heat until the sugar has dissolved.
Bring to a boil and cook for 2 minutes.
Remove from heat and cool slightly. In a medium bowl, beat 2 egg whites until stiff peaks form.
Gradually add the sugar syrup to the beaten egg whites, mixing until all of the syrup has been absorbed. Spread frosting over the cooled cake.
Enjoy!