tina's rhubarb cake

Ingredients

• 1 1/2 cups brown sugar, firmly packed
• 1/2 cup butter or butter flavored shortening
• 1 - egg
• 2 cups all purpose flour
• 1 teaspoon baking powder
• 1 teaspoon baking soda
• 1/2 teaspoon salt
• 1 cup sour milk (1 tbsp vinegar in 1 cup milk, let rest 5 minutes)
• 1 1/2 cups raw rhubarb sliced thinly
• TOPPING
• 1/2 cup brown sugar, firmly packed
• 1 teaspoon ground cinnamon
• 1/2 cup chopped nuts