||Yield: one 9x13-inch pan
1/2 cup butter, softened
1 1/2 cups brown sugar
1/2 tsp salt
1/2 cup buttermilk (see note below)
1/2 cup sour cream
1 tsp baking soda
1/2 tsp baking powder
1 tsp vanilla extract
2 1/4 cup white flour
2 cups raw, sliced rhubarb (Update - May 15, 2012 -- I've increased the rhubarb to 2 cups from 1 3/4 cups due to personal preference)
3 tbsp white sugar
1/2 tsp cinnamon
1/2 tsp nutmeg
Preheat oven to 375F. Grease a 9x13-inch baking pan and set aside.
In a large bowl, cream butter and brown sugar until smooth. Add egg and salt. Stir in buttermilk, sour cream and vanilla.
In a medium bowl, blend together the flour, baking soda and baking powder. Mix and add to the butter mixture. Gently fold in the rhubarb. Pour (batter will be very thick) batter into the prepared pan.
Combine white sugar, cinnamon and nutmeg in a small bowl. Sprinkle over batter. Bake for 35 minutes or until a toothpick inserted into the centre comes out clean.
Note: I never buy real buttermilk. Instead, I add white vinegar to 1% milk (1 tbsp of vinegar for every 1 cup of milk). Let it sit for 5-10 minutes and voila! An easy (and slightly chunky) substitute for buttermilk. Don't let the wee chunkies scare you.
Tip: This recipe could easily be made into muffins. Just decrease the baking time (try 15-20 minutes at 375F).