Preheat the oven to 400 degrees F. Line a baking sheet with parchment paper.
Place the chopped pecans in a medium bowl. Add the maple syrup, chipotle chile powder, cinnamon and salt. Toss to coat the pecans.
Spread the pecans in a single layer on the prepared baking sheet.
Bake until the pecans are just golden brown, 7 to 8 minutes. Take care not to brown them too much because they will be browned additionally when the casserole is baked.
The sweet potatoes:
Line a baking sheet with foil. Keep the oven at 400 degrees F.
Scrub the sweet potatoes, then pat dry. Pierce each potato with a fork in 6 or 7 places. Place on the prepared baking sheet.
Bake until the potatoes are very tender when pierced with a fork, 50 minutes to 1 hour.
Turn the oven heat to 350 degrees F. Lightly coat a 1 ½ quart baking dish with cooking spray. You can also use a deep pie dish or 8- by 8-inch baking dish.
Place the potatoes on a cutting board and allow them to cool slightly before handling. Cur the potatoes in half lengthwise. Scoop the flesh out and place into a large bowl.
To the sweet potato flesh, add the coconut milk (or alternative). With a hand mixer, mix until the potatoes are very smooth. Add the maple syrup, cinnamon, ginger, salt, nutmeg and chipotle chile powder. Mix again until combined.
Transfer the sweet potato mixture to the prepared baking dish and smooth the top. Sprinkle the topping evenly over the potatoes.
Bake until the topping is light golden brown and the potatoes are heated through, 20 to 25 minutes.
In a bowl, combine the chipotle pecans, oats, flour, sugar and melted coconut oil. Toss to until the ingredients are completely combined.