Sweet Potato Casserole

Method

1. Preheat the oven to 375°F (190°C). Grease a 2 to 2½ quart baking dish — a rectangle or oval is best so there's plenty of surface area for the topping.
2. Drop the sweet potato chunks into a large pot, cover with cold water, and bring to a boil. Cook until tender, around 7 minutes depending on size. Drain well and return to the pot.
3. Add the butter, milk, brown sugar, cinnamon, and a pinch of salt to the warm potatoes. Mash to your liking — chunky or completely smooth, your call. Taste and adjust the seasoning.
4. Spread the mashed potatoes evenly into the prepared dish. (You can stop here if you're prepping ahead — cool, cover, and refrigerate up to 2 days.)
5. Slide the dish into the oven and warm the potatoes through. From room temp this takes 5–10 minutes; from the fridge, closer to 30. Meanwhile, make the streusel.
6. In a medium bowl, mash together the softened butter, brown sugar, flour, cinnamon, and salt with a fork or spatula until clumpy. Stir in the chopped pecans.
7. Pull the warm dish from the oven. Scatter half the marshmallows over the top, then pinch streusel into rough clumps and dot half of it across the surface. Add the remaining marshmallows, then the rest of the streusel.
8. Return to the oven for 8 to 15 minutes, until the topping is golden and the marshmallows are toasted. Watch closely — the line between toasted and torched is short. Slide briefly under the broiler if you want more colour.
9. Rest at room temperature for a few minutes before serving.