Heat oven to 350°F. Spray a bundt pan with no-stick cooking spray; set aside.
Combine sugar, butter and vanilla in bowl; beat at medium speed until creamy. Add 1 egg at a time, beating well after each addition.
Place 1 cup batter into another bowl; set aside.
Add pumpkin to remaining batter in bowl; beat at medium speed until well mixed.
Add 1 3/4 cups flour, 1 teaspoon baking powder, salt, cinnamon, nutmeg and cloves. Beat at low speed until well mixed.
Spoon half of pumpkin batter into prepared pan.
Add melted chocolate to reserved 1 cup batter; beat at medium speed until smooth.
Add remaining 1/2 cup flour and 1/2 teaspoon baking powder; continue beating until well mixed.
Add buttermilk; beat until well mixed.
Drop chocolate batter by tablespoonfuls over pumpkin batter in pan. Top with remaining pumpkin batter; spread to edges of pan.
Swirl chocolate batter into pumpkin batter with a table knife.
Bake 50-60 minutes or until a few moist crumbs cling to toothpick inserted into center.
Cool in pan 10 minutes. Invert onto serving plate; cool completely.
Pour whipping cream in 2-cup glass measuring cup; microwave 45-50 seconds or until mixture comes to a boil; add chocolate chips. Let stand 1 minute; stir until smooth. Spread glaze over top of cake and enjoy!