Boil the sweet potatoes: Place peeled, cubed sweet potatoes in a large pot of salted water and boil until fork-tender, about 15-20 minutes. Drain thoroughly and let steam off for a few minutes to remove excess moisture.

Mash until smooth: Transfer the drained sweet potatoes to a large bowl and mash with a potato masher until smooth with no large lumps remaining.

Mix in flavor: Add maple syrup, melted butter, eggs, cinnamon, nutmeg and salt to the mashed sweet potatoes. Beat until the mixture is glossy and well combined.

Preheat the oven: Preheat the oven to 350°F and lightly grease a 9x13-inch baking dish with butter or nonstick spray.

Spread the filling: Pour the sweet potato mixture into the prepared baking dish and smooth the top evenly with a spatula.

Make the pecan topping: In a separate bowl, combine chopped pecans, brown sugar, flour and melted butter. Mix with a fork or your fingers until it forms a clumpy, sand-like texture.

Add the topping: Sprinkle the pecan mixture evenly over the sweet potato filling, covering it completely for even browning.

Bake until golden: Bake uncovered for 30-35 minutes, until the topping is deep golden brown and the edges of the filling are bubbling.

Rest before serving: Let the casserole rest for 10 minutes before serving so the filling sets enough to hold a clean scoop.