Instructions

  1. Set oven to 350 degrees F.
  2. Grease a 13 x 9-inch baking dish.
  3. In a small bowl using fingers mix together the topping ingredients until crumbly; set aside.
  4. In a large bowl cream 1/2 cup butter with sugar until fluffy (about 2 minutes).
  5. Add in egg and vanilla; beat until well combined.
  6. In a small bowl mix together 2 cups flour with baking soda, salt and a pinch of nutmeg; add to the creamed mixture alternately with buttermilk.
  7. Toss the chopped rhubarb with 1 tablespoon flour then stir into the batter along with the walnuts.
  8. Sprinkle the prepared topping mixture evenly over the top of the batter.
  9. Bake for about 45-50 minutes.
  10. Serve cake warm with vanilla ice cream or whipped cream.