Rhubarb Cake
["1/2 c. unsalted butter", "1 1/4 c. light brown sugar", "2 eggs", "1 tsp. vanilla", "2 Tbsp. cinnamon", "1 1/2 c. sifted cake flour", "1 tsp. baking soda", "2/3 c. buttermilk, yogurt or sour cream", "1 1/2 c. rhubarb, cut into 1/2-inch pieces", "1/4 c. granulated sugar"]
["Cream butter with brown sugar until light and fluffy.", "Beat in eggs, one at a time.", "Then beat in vanilla and 1 tablespoon cinnamon.", "Sift flour and baking soda and beat mixture into butter mixture in 3 parts, alternating with buttermilk.", "Fold in rhubarb. Pour batter in standard 8 x 8 x 2-inch glass baking dish.", "Blend sugar and remaining cinnamon and sprinkle over top.", "Bake until toothpick comes clean, 45 minutes at 375\u00b0.", "Top with whipped cream."]
["unsalted butter", "light brown sugar", "eggs", "vanilla", "cinnamon", "cake flour", "baking soda", "buttermilk", "rhubarb", "granulated sugar"]