01 -
Preheat oven to 175°C (350°F). Grease a 23x33 cm (9x13-inch) baking dish.
02 -
Place sweet potatoes in a large pot, cover with water, and bring to a boil. Cook until tender, about 15 minutes. Drain and mash in a large bowl.
03 -
Add melted butter, sugar, eggs, milk, vanilla, cinnamon, and salt to the mashed sweet potatoes. Mix until smooth and creamy.
04 -
Spread the sweet potato mixture evenly in the prepared baking dish.
05 -
In a separate bowl, combine flour, brown sugar, oats (if using), cinnamon, and salt. Stir in melted butter until the mixture resembles coarse crumbs, then fold in the pecans.
06 -
Sprinkle the cinnamon crunch topping evenly over the sweet potato layer.
07 -
Bake for 35–40 minutes, or until the topping is golden brown and the casserole is bubbling at the edges.
08 -
Let cool slightly before serving.