Preheat oven to 300º. Heavily grease and flour a 10” bundt pan.
Cream butter in a large mixing bowl; gradually add sugar, beating well at medium speed of an electric mixer. Add eggs, one at time, beating after each addition.
Dissolve soda in buttermilk, stirring well. Add to cream mixture alternately with flour. Add 1 cup chocolate chips, melted chocolate, chocolate syrup, and vanilla, stirring until just blended.
Spoon batter into prepared pan. Bake for 1-1/2 hours or until cake springs back when touched. Invert cake immediately onto a serving plate and let cool completely.
Combine chopped white chocolate and 2 tablespoons of shortening in top pf a double boiler; Cool until mixture is melted and smooth. Remove from heat. Drizzle melted white chocolate over cooled cake. Melt remaining ½ cup of chocolate chips with 2 teaspoons of shortening in a small saucepan over low heat, stirring until smooth. Remove from heat, and let cool; drizzle over white chocolate.