Pecan Streusel Coffee Cake

This recipe was inspired from one in the April issue of Bon Appétit. It uses Greek yogurt (it's much thicker than regular yogurt) in place of the more common sour cream. I used a springform pan, which worked very well because it's a fluffy cake. This would be even better with homemade caramel sauce drizzled on top.

Pecan Streusel Coffee Cake
1/2 cup butter, softened
1 1/3 cups dark brown sugar
1 tsp. vanilla
2 eggs
2 cups all-purpose flour
1 1/4 tsp. baking soda
1/2 tsp. salt
1 tsp. allspice
1 cup Greek-style plain yogurt
1 cup pecans, toasted and chopped
2/3 cup dark brown sugar
2/3 cup all-purpose flour
1/2 tsp. cinnamon
1/2 cup butter, melted

1. Beat butter and 1 1/3 cups brown sugar until light and fluffy. Beat in vanilla. Beat in eggs, 1 at a time, until yellow disappears.
2. Combine 2 cups flour and next 3 ingredients. Gradually add to butter mixture alternately with yogurt, beginning and ending with flour mixture. Stir in pecans.
3. Pour batter into a lightly greased springform pan. In a separate bowl, stir together 2/3 cup brown sugar, 2/3 cup flour, and next 2 ingredients. Dollop mixture over top of batter in springform pan.
4. Bake at 350° for 45 minutes or until done. Let cool in pan 30 minutes; release sides of pan to serve.