Sweet Potato/Pumpkin Souffle

filling:
3 C. cooked and mashed sweet potatoes
1 C. Sugar (I normally don't use sugar with sweet potatoes, and I use only 1/2 cup for pumpkin)
2 eggs
1/2 c. milk
1/2 t. salt
1 t. vanilla

Topping:
1 C. Brown Sugar
1/2 c. flour
1 c. chopped nuts
1/2 stick room temp butter

Combine filling and pour into buttered pan. Crumble combined topping over top.
Bake at 400 for 30-40 min.