To roast the butternut squash.

1. Preheat the oven to 400°
2. Toss the chunks of butternut squash with the salt, sugar and the vegetable oil. Spread evenly on a Silpat lined or a greased cookie sheet.
3. Roast for 45 minutes until the edges of the squash are dark gold or even brown, to concentrate the flavors and cook out some of the moisture.
4. Let the squash cool completely.
5. Puree the squash in a food processor or a blender.
6. You should have about 1 cup of very thick puree. If it is a bit more that is ok.

Note: You can roast the squash the day before and puree it when you are ready to bake, or you can puree it and store it in the fridge overnight

When you are ready to bake the coffeecake:

1. Grease or butter a 9 X 13 pan

To make the topping

1. In a medium bowl combine the flour, brown sugar, cinnamon, ground coriander, salt, and chopped pecans. You may need to rub the brown sugar into the flour to get it to combine. You don’t have to get all the lumps out.
2. Stir the vanilla into the melted butter.
3. Combine the melted butter with the flour mixture. The mixture should be big crumbles.
4. Set aside.

To make the batter.

1. In a medium bowl or a 4 cup measuring cup, stir together the flour, baking soda, baking powder, cinnamon, ground coriander, grated nutmeg, the pinch of cloves, and the salt.
2. In a large bowl of a mixer, beat the butter and the sugar until very light and creamy, It should take several minutes. You can do this by hand, it just takes some muscle.
3. Scraping down the bowl after each addition, beat in the eggs one at a time.
4. Beat in the sour cream, the butternut squash puree, and the vanilla.
5. Using a spatula or a big spoon stir the flour mixture into the beaten butter, just until everything is combined.
6. Spread the batter into the prepared pan.
7. Crumble the topping evenly over the batter, making sure to cover the entire surface with the crumbs.
8. Bake for 35-40 minutes.