JamieOliver.com

Ingredients
1/4 cup butter, softened
1 1/2 cups packed brown sugar
1 egg
1 tablespoon vanilla extract
2 1/3 cups all-purpose flour
1 teaspoon baking soda
1/2 teaspoon salt
1 cup yogurt (I used low fat and it still came out amazingly tender and moist!)
4 cups chopped rhubarb
1/4 cup white sugar
1/4 teaspoon ground nutmeg
1/4 teaspoon ground cinnamon
powdered sugar
In large bowl, cream together butter or margarine and brown sugar. Beat in egg and vanilla.
Sift or stir together flour, baking soda and salt; gradually stir in to butter mixture. Fold in yogurt and rhubarb. (note: the batter will seem very thick, almost like cookie dough; this is how it is supposed to be!) Spoon batter into greased and floured baking pan.
Stir together white sugar and spices; sprinkle over batter.
Bake at 350 degrees F (175 degrees C) for 40 minutes, or until tester comes out clean. (Mine only took 30 minutes because I used a large baking pan.)
Sprinkle with a little bit of powdered sugar.
Cut into squares when cool. (actually, i couldn't wait and cut a piece to try while it was still warm...sooo delicious!)

This simple and oh-so-delicious cake is incredibly tender and moist, and has the most lovely balance of sweet and sour. Though humble-looking, it's taste is anything but!

Method
In large bowl, cream together butter or margarine and brown sugar. Beat in egg and vanilla.
Sift or stir together flour, baking soda and salt; gradually stir in to butter mixture. Fold in yogurt and rhubarb. (note: the batter will seem very thick, almost like cookie dough; this is how it is supposed to be!) Spoon batter into greased and floured baking pan.
Stir together white sugar and spices; sprinkle over batter.
Bake at 350 degrees F (175 degrees C) for 40 minutes, or until tester comes out clean. (Mine only took 30 minutes because I used a large baking pan.)
Sprinkle with a little bit of powdered sugar.
Cut into squares when cool. (actually, i couldn't wait and cut a piece to try while it was still warm...sooo delicious!)