Preheat oven to 375°F. Lightly grease an 8×8 baking dish.
Toss the chopped sweetpotatoes with the olive oil. Spread onto a baking sheet and bake at 375°F for 15-20 minutes on the center rack, stirring once halfway, until sweetpotatoes are just tender.
In a large mixing bowl, combine the roasted sweetpotatoes, blueberries, coconut sugar, corn starch, lemon juice, vanilla, cinnamon, and salt. Pour into the prepared baking dish.
In another mixing bowl, combine the oats, almond flour, pecans, coconut sugar, and salt. Stir a few times, then add the olive oil and stir until well combined. Pour the topping evenly over the sweetpotato-blueberry mixture.
Bake at 375°F for 25-30 minutes, or until the filling is warm and bubby and the topping is golden brown.
Let cool for a few minutes, then serve warm. Optionally add your favorite toppings, like non-dairy or dairy-based versions of vanilla ice cream, yogurt, or whipped cream (depending on your diet and preferences).