Preheat oven to 350°.
Place squash in a large microwave-safe bowl and microwave for approximately 5 minutes, or until squash is cooked. Alternatively, you can roast the squash in the oven at 400° for 25 minutes.
Next, whisk melted coconut oil, milk, eggs, and vanilla together in a bowl and set aside.
Use a potato masher or fork to mash butternut squash similarly to how you would mash bananas in banana bread, then pour wet ingredients into the bowl with the mashed squash and stir to combine; set aside.
In a separate bowl, combine flour, sugar, baking powder, and baking soda. Pour dry ingredients into wet ingredients and use a large spoon to stir everything together. Last, stir in the chopped pecans.
Grease a bread pan with coconut oil and pour batter into the bread pan, using a spatula to smooth batter out.
Bake bread for 45-55 minutes, or until the edges are golden and a toothpick comes out clean. Leave bread in the pan for 10 minutes, and then run a knife along the edges and carefully invert bread onto a cooling rack.
For the glaze: whisk sugar and milk together and then pour glaze over bread.
Slice and enjoy!