Preheat oven to 375ºF and line a rimmed baking sheet with parchment paper.
In a large pot place cubed sweet potatoes and cover with water. Cover and let boil for 15 minutes or until fork-tender.
Meanwhile, make quick candied pecans: Heat a skillet over medium high heat and add 1 cup pecans. Toast until fragrant, about 30 seconds. Carefully add maple syrup and mix to coat all pecans. Once the maple syrup is boiling, remove from heat, and spread on the baking sheet to cool.
Drain potatoes and return back to the pot. To the sweet potatoes add maple syrup, butter, cinnamon, nutmeg vanilla and salt mash together until mostly smooth. If adding raisins, add in now. Alternatively you could pulse this in a food processor or high-speed blender if you want an ultra smooth filling.
Scoop the mashed sweet potato into your Baking dish and smooth over the top.
Garnish the sweet potato casserole with the pecans.
Bake in the preheated oven for 20 minutes and serve warm.