01 - Preheat your oven to 350°F (180°C). Lightly grease a 9x13-inch (23x33 cm) baking dish.
02 - Place the cubed sweet potatoes in a large saucepan, cover with water, and bring to a rolling boil. Cook until they are tender when pierced with a fork, approximately 12–15 minutes. Drain thoroughly.
03 - In a large bowl, mash the cooked sweet potatoes until smooth. Incorporate the melted butter, maple syrup, milk, eggs, vanilla extract, cinnamon, nutmeg, and salt. Stir until the mixture is uniformly creamy and well combined.
04 - Spread the sweet potato mixture evenly into the prepared baking dish.
05 - In a separate bowl, combine the flour, brown sugar, melted butter, pecans, maple syrup, cinnamon, and a pinch of salt. Mix until the ingredients form a crumbly texture.
06 - Evenly sprinkle the pecan topping over the sweet potato base.
07 - Bake for 35–40 minutes, or until the topping achieves a golden-brown hue and the filling is set. Allow the casserole to cool for 10 minutes before serving.