This is a favorite of my mom's. She grew rhubarb in her garden and was famous in her neighborhood for her rhubarb pie and cakes. The sour cream makes this a more moist cake compared to other recipes, while the topping gives it an extra taste of sweetness.
Preheat the oven to three hundred and seventy-five degrees. Grease a cake pan and line with parchment paper.
In a large mixing bowl, using an electric mixer, combine one-half cup of butter and one and one-half cups of white sugar.
Add two eggs, one cup of sour cream and one teaspoon of vanilla. Mix until well combined.
Mix in two cups of Bisquick, and one teaspoon of baking soda. Do not over mix.
Stir in two cups of rhubarb. Pour batter into the prepared cake pan and prepare the topping.
In a small mixing bowl add one-half cup of brown sugar, one tablespoon of Bisquick, one tablespoon of cinnamon and one tablespoon of soft butter. Mix until crumbly and sprinkle over the top of the cake batter.