Rhubarb Coffee Cake

1/2 cup butter, softened
1 cup packed brown sugar
2 eggs
1 tsp vanilla
2 cups all purpose flour
1 tsp baking powder
1 tsp baking soda
1/2 tsp salt
1 cup buttermilk
2 cups chopped rhubarb

Topping:

1/2 cup packed brown sugar
1/4 cup chopped hazelnuts, pistachios, or sliced almonds
1 tbsp all-purpose flour
1/2 tsp cinnamon
2 tbsp butter, melted

Grease 9-inch springform pan; set aside.

Topping: In bowl, combine brown sugar, chopped hazelnuts, flour and cinnamon. Using fork, stir in butter until crumbly; set aside.

In large bowl, beat buter with brown sugar until light and fluffy; beat in eggs, 1 at a time. Beat in vanilla. In separate bowl, whisk together the flour, baking powder, baking soda and salt. Add to butter mixture alternately with buttermilk, making 3 additions of flour and 2 of buttermilk. Fold in chopped rhubarb. Scrape into prepared pan; sprinkle with topping.

Bake in centre of 350 F oven until cake tester inserted in centre of cake comes out clean, about 1 1/4 hours. Let cool in pan on rack for 5 minutes. Remove side of pan. Serve warm or cool. Makes 8 to 10 servings.

Source: Canadian Living Magazine, June 2005