Bake the Sweet Potatoes:

1. Adjust the cooking rack to the lowest position and preheat toaster oven to 400°F on the BAKE setting.
2. Slice sweet potatoes in half lengthwise, add to a baking sheet and drizzle with oil. Use your hands to rub the oil over the skins and flesh.
3. Bake sweet potatoes (with the cut side facing the pan) until fork-tender, about 25 to 30 minutes.
4. Once cooked, remove the pan from the toaster oven and allow the sweet potatoes to cool for 5 minutes. Reduce the temperature to 375°F and leave the toaster oven on.

Make the Streusel:

1. Roughly chop the pecans. Combine the chopped pecans, oats, brown sugar, flour, cinnamon, and salt in a medium bowl. Add the butter and use your fingertips to work the butter into the oat mixture until it forms into small clumps.
2. Refrigerate streusel until the sweet potatoes are ready for topping.

Assembly:

1. Flip the cooled sweet potatoes over and sprinkle with cinnamon and nutmeg. Use a fork to gently mash the flesh and combine the seasoning.
2. Distribute crumble topping evenly over the sweet potatoes.
3. Return pan to the toaster oven and bake until the streusel is lightly browned and crispy, about 15 minutes. Cool slightly before digging in!