Preheat the oven to 400 degrees F.
Place the potatoes in a single layer on a baking sheet and place them in the center of the oven. Cook until the potatoes are completely yielding in the center when pierced with the tip of a knife, 45 minutes to 1 hour, depending on the size of a potato. Remove from the oven and lower the temperature to 375 degrees F.
Place the potatoes on a flat surface and use a sharp knife to cut down the middle of them lengthwise. Use a tablespoon to scoop out the flesh, leaving the skin behind. Transfer the flesh to a medium, oven proof dish. Stir it slightly to break up any large pieces and place the dish in the oven. Bake in the oven for 10 minutes and give the flesh a stir again. Bake for an additional 10 minutes. Remove from the oven.
In a small saucepan, warm the cream. Transfer the sweet potato flesh to a medium bowl and whisk in the 1 tablespoon butter and cream. Season with salt, to taste.
Heat a skillet and add the remaining 1 stick butter. Allow it to melt and turn light brown. Transfer to a bowl to stop it from overbrowning. Stir in the orange juice, orange zest, sherry, and molasses. Taste for seasoning. Serve immediately with the potatoes.