Preheat oven to 350°F.
Cream butter and sugar together in mixing bowl.
Beat in eggs one at a time.
Stir in sour cream and vanilla.
Mix flour and baking soda together and fold into batter.
Stir in rhubarb.
Turn into greased 9x13-inch pan.
Topping: Mix all ingredients together until crumbly.
Sprinkle over top.
Bake 30-40 minutes until done.
