My mom and grandma would make this cake every spring as the rhubarb was starting to fill out. It’s not keto (though I make it with gluten free flour these days), but it is an amazing treat ushering in spring/summer:
1 1/2 cups brown sugar
1/2 cup butter (softened)
1 cup buttermilk
2 cups flour (gluten free mix works)
1 teas. baking soda
1/2 teas. salt
1 teas. vanilla
4 cups rhubarb, chopped into small pieces
1/4 cup sugar (or monk fruit works)
1 T. ground cinnamon
Heat oven to 350 degrees F.
Cream together brown sugar and butter. Beat in egg and buttermilk. Mix dry ingredients together; add to butter/sugar mixture and mix well. Stir in rhubarb. Pour into a greased 9×13 cake pan.
Mix sugar and cinnamon for topping; sprinkle over cake.
Bake for 25 – 35 minutes or until wooden pick inserted in the center comes out clean.