Sweet Potato Casserole

I love sweet potatoes. I could eat them almost every day without complaining, but I never really cared for the traditional candied recipe...you know the one with marshmallows?
When I was living down south, I was introduced to this fantastic recipe, and I can't for the life of me recall who gave it to me, but I cannot have Thanksgiving without it. I have one family member that tells me he won't come to my house for dinner unless this is on the menu.
It is that good. I have found myself eating it in place of dessert at times, because it is almost like a sweet potato pie without the crust.
This recipe makes a big casserole, so you can cut it in half for smaller meals.

Ingredients:
4 1/2 C (about 4 medium) cooked, mashed sweet potatoes ( I'm not too proud to admit that I have cheated and used canned)
1 C sugar
2 eggs
1 1/2 tsp pure vanilla
1/4 C buttermilk ( add 1 tsp vinegar or lemon juice to milk and let sit for 5 minutes to make buttermilk)
1/2 C melted butter

Topping ingredients:
1/3 C (42 g) gluten free all-purpose flour 
1 C chopped pecans
1/3 C melted butter
1 C packed brown sugar

Preheat your oven to 375*F and grease a 2 quart casserole dish, or 9x13 pan.

1.In a large bowl, mix together your casserole ingredients and pour into the casserole dish.

2. Bake for about 30 minutes, or until it has firmed up in the center when you jiggle it.

3. Combine your topping ingredients in a small bowl and sprinkle over the top of your casserole. Place back into the oven for another 10-15 minutes, or until the topping has cooked a bit. It should look like pralines, and be a bit crunchy.

4. Remove from the oven and let it sit for about 20 minutes, because that topping is lava hot right out of the oven, and I don't want you to burn the roof of your mouth.