Peel and chop the sweet potatoes into large chunks and place them in a large saucepan. Cover fully with water and bring to a boil over high heat. Reduce to a simmer and simmer for about 15 minutes or until fork tender. Drain and set aside.
Preheat oven to 375 degrees. Rub a small amount of extra virgin olive oil to coat the inside of a 9 x 9 or 9 x 13 casserole dish.
In a mixing bowl, combine all of the crumble topping ingredients. Mash in the solid coconut oil (or vegan butter) until the chunks are broken up and it looks like a crumble.
In a large bowl mash the sweet potatoes with a fork before adding the coconut milk, maple syrup, flaxseed, vanilla, cinnamon, nutmeg, and salt to the bowl. Mix until everything is combined.
Pour sweet potato mixture into the prepared casserole dish and sprinkle on the oat pecan crumble topping.
Bake uncovered for approximately 25 minutes or until the topping is golden brown and the sweet potatoes are bubbling.
Serve and enjoy!

Sweet Potato Casserole with Oat Pecan Crumble