Rhubarb Crumb Coffee Cake

Directions

1. In a large bowl, cream butter and sugar until light and fluffy. Add eggs, one at a time, beating well after each addition. Beat in vanilla. Combine the dry ingredients; add to creamed mixture alternately with buttermilk. Stir in rhubarb. Pour into a greased 13x9-in. baking dish.
2. In a small bowl, combine the flour, brown sugar and cinnamon. Cut in butter until mixture resembles coarse crumbs. Sprinkle over batter.
3. Bake at 350° for 45-55 minutes or until a toothpick inserted in the center comes out clean. Cool on a wire rack.