A little note about finding sweet potatoes in Lyon, France: In the old days, you had to go the African or Asian markets at the Guillotière or the 'exotique' section of Carrefour to find them. But as of 2008 you can find them easily in most grocery stores (Monoprix, Ed, Casino, Intermarché...) in the produce section. Thay are called 'patates douces' and often come from Israel.
4 cups sweet potatoes (cooked, peeled, and mashed)
2 Tbsp butter
2 eggs, beaten
1/2 cup milk
1 teaspoon vanilla
1/4 cup sugar
1/2 cup brown sugar
1 cup coconut
3 tablespoon butter, melted
In a large mixing bowl, combine mashed sweet potatoes, margarine, eggs, milk, vanilla and sugar. Mix well. Spread into a greased 1 1/2-quart casserole.
Prepare the topping by mixing the coconut, brown sugar and butter. Sprinkle over the potatoes.
Bake at 350 degrees for 35-40 minutes, until potatoes are set and toppings browned and crispy.