Step 1 – Prepare the squash
Preheat the oven to 190°C (375°F). Cut a small butternut squash in half, remove the seeds, and bake, flesh-side down, until very tender. Let it cool slightly, then roughly mash the flesh with a fork. Set aside.
Step 2 – Streusel
In a bowl, combine the pecans, flour, brown sugar, cinnamon, and salt. Add the cold butter and maple syrup. Work the mixture with your fingertips until it resembles coarse sand. Refrigerate.
Step 3 – Cake Batter
Preheat the oven to 180°C (350°F). Butter a round or rectangular baking tin.
In a bowl, mix the flour, baking powder, baking soda and salt.
In another bowl, whisk the eggs with the brown sugar, oil, and vanilla. Stir in the pumpkin puree. Add the dry ingredients alternately with the milk, mixing gently.
Step 4 – Assembly
Pour the batter into the mold. Spread the streusel evenly over the entire surface, pressing lightly.
Step 5 – Cooking
Bake for about an hour, or until a toothpick inserted in the center comes out clean. Let cool before unmolding.