If you are not fond of marshmallows on top of your Thanksgiving Sweet Potatoes try this streusel topping instead. This should make enough for a 9x13 dish. This is from Cook's Illustrated.
1/2 cup flour
1/2 cup packed brown sugar
1/4 tsp salt
5 tablespoons unsalted butter, cut into 5 pieces and softened, plus a little extra for
greasing the pan
1 cup pecans
Butter the dish. Pulse flour, brown sugar, and salt in food processor until blended, about 4 1 second pulses. Sprinkle butter pieces over flour mixture and pulse until crumbly mass forms, six to eight 1 second pulses. Sprinkle nuts over mixture and pulse until combined but some large nut pieces remain, four to six 1 second pulses. Sprinkle topping over sweet potatoes, breaking up any large pieces with fingers. The original recipe says to bake til topping is well browned and filling is slightly puffed around the edges about 40 min and baking at 375 degrees.
Depending on what type of filling you use the baking time may vary. If you oven tends to run hot you may want to reduce the temperature to 350 degrees.