3 lbs fresh sweet potatoes (4–5 large sweet potatoes), peeled and cut into 1 inch cubes
1/2 cup (120ml) milk
1 cup (225g) packed light brown sugar
1/4 cup (56g) unsalted butter, melted
1 tsp ground cinnamon
1/2 tsp ground nutmeg
1 tsp vanilla extract
Pinch of salt
Preheat oven to 350°F (176°C).
Put the sweet potatoes in a large pot and cover with water. Bring the water to a boil and boil until the potatoes are fork tender, about 8 minutes.
Drain the potatoes and return to the pot. Mash the potatoes until they are your desired level of smoothness.
Add the milk, brown sugar, butter, eggs, cinnamon, nutmeg, vanilla and salt to the potatoes and stir until well combined.
Pour the potatoes into a 9×13 casserole dish. At this point you can cover the dish and refrigerate for up to two days before cooking, or you can put them in the oven right away. Heat them until cooked through, 25-30 minutes (might take less time if you’re cooking them right away).
While the potatoes are cooking (or you could also prepare this ahead of time), combine the flour, brown sugar, cinnamon, nutmeg and cloves for the streusel topping.
Add the melted butter and stir until well combined.
When the casserole is heated through, remove it from the oven and top it with the marshmallows and streusel. I like to add some marshmallows, then the streusel, then the remaining marshmallows.
Bake for another 10-15 minutes. If you want to brown the marshmallows a little more, turn the oven to the broil setting at 400 degrees until they’ve browned to your liking. Serve casserole warm.