This looked tasty, and it had a typo...so I just had to adopt and fix it!
1 1/2 c
egg, slightly beaten
brown sugar, firmly packed
1All ingredients should be at room temperature.
2In a bowl, mix together flours, soda and baking powder.
3In another bowl cream together butter with sugar until fluffy and light.
4Add egg and vanilla and mix well.
5Add half of dry ingredients, mixing just until flour is blended.
6Blend in sour cream, then remaining dry ingredients.
7Spread half of batter lightly into a 10-inch tube pan.
8Sprinkle with half of topping and spread with remaining batter.
9Sprinkle with remaining topping.
10Bake at 350 degrees 40 to 45 minutes.
11TOPPING: Mix together flour, sugar, salt and nuts.
12Add butter in small pieces.
13Rub in by hand until mixture is crumbly.
14Be careful not to overmix.