1 cup pitted prunes, cut into small pieces
1 cup coarsely chopped walnuts
2 cups sifted all-purpose flour
1 tsp baking soda
1-1/2 tsp ground cinnamon
1-1/2 tsp ground nutmeg
1 tsp ground allspice
1/4 tsp salt
2 cups sugar
1 cup vegetable oil
1 cup buttermilk
2 tsp vanilla
3 eggs

Unsweetened whipped cream for garnish

1. Preheat oven to moderate (350 degrees). Generously grease and flour 9-inch (12-cup) Bundt pan.

2. Combine the prunes with the walnuts and 1/2 cup of the flour in a bowl.

3. Sift together the remaining 1-1/2 cups of flour with the baking soda, cinnamon, nutmeg, allspice and salt into a large bowl. Add the sugar, oil, buttermilk, vanilla and eggs. Beat with an electric mixer at medium-high speed for about 1 minute or until the flour mixture is creamy smooth. Add the prune mixture and fold it in lightly but thoroughly. Pour the batter into the prepared pan.

4. Bake in the preheated moderate oven for 45-50 minutes or until the cake pulls away from the sides of the pan and is springy to the touch. Cool the cake upright in the pan on a wire rack for 15 minutes. 

5. Prepare the Sweet Butter Glaze.

6. Loosen the cake around the edges with a thin-bladed spatula and invert the cake onto the wire rack. Pierce the cake all over with a wooden pick. Set the wire rack with the cake on it, over a large, round platter. Slowly ladle the glaze evenly over the cake.

Sweet Butter Glaze:
Combine 1/2 cup of granulated sugar, 1/2 cup of buttermilk, 1/2 tsp of baking soda and 1/4 cup (1/2 stick) of unsalted butter in a saucepan. Cook over medium heat, stirring occasionally, until the butter melts and the mixture boils. Remove the glaze from the heat.

7. Garnish each slice with a dollop of whipped cream.