Cake:

• 2 cups (270g) uncooked butternut squash, peeled, cut into 1/2 inch cubes
• 2 tsp vegetable oil
• 12 tbsp (1 ½ sticks, ¾ cup) unsalted butter
• 2 cups (280g) all-purpose flour
• 1 ½ tsp baking soda
• ½ tsp salt
• 1 tsp cinnamon
• 1 tsp ginger
• 1 tsp nutmeg
• 1 tsp all-spice
• ¼ tsp cloves
• 1 ½ (300g) cups granulated sugar
• ⅔ cup (100g) packed dark brown sugar
• 2 large eggs, room temperature
• ¼ cup 35% whipping cream

Frosting:

• 8 tbsp (1 stick, ½ cup) unsalted butter
• 2 tbsp boiled water
• 1 cup (150g) dark brown sugar
• ¼ cup 35% whipping cream
• 2 cups (250g) icing sugar

1. Preheat the oven to 350°F.
2. Butter 2 8-inch round cake pans and line the bottoms with parchment paper.  Set aside.
3. Place the peeled, chopped butternut squash in a microwave-safe bowl and cook for 5 minutes, until soft.
4. Transfer the softened butternut squash to a food processor.
5. Add the vegetable oil.
6. Pulse until it becomes a smooth purée.  You will end up with 1 1/2 cups of butternut squash purée.  Set aside.
7. Melt the butter over low heat in a small saucepan.
8. Raise the heat to medium and cook the butter until it turns golden brown and releases a nutty aroma.  It will bubble, and there will be little dark flecks at the bottom of the saucepan.
9. Remove the saucepan from the heat and transfer the browned butter to a small heat-proof bowl.  Set aside.
10. In a small bowl, whisk the flour, baking soda, salt, cinnamon, ginger, nutmeg, all-spice and cloves together.  Set aside.
11. In a large bowl, whisk the butternut squash purée, eggs,granulated sugar, dark brown sugar and the cream together until combined.
12. Pour the browned butter into the batter, and whisk until smooth.
13. Use a spatula to gently fold the flour mixture into the butternut squash mixture.  Be careful not to overmix the batter!
14. Divide the batter evenly between the two prepared pans.
15. Bake for 33 minutes, or until the moist cake springs back when you touch the top lightly with your fingers.
16. Transfer the pans to a wire rack and let the cakes cool for 10 minutes in the pans.
17. Flip the cakes out of the pans and let cool completely on the wire rack.
18. For the penuche frosting, melt the butter in a medium saucepan.
19. Add the brown sugar to the saucepan.
20. Bring the mixture to a boil for 2 minutes, stirring constantly.
21. Add the 2 tbsp of boiled water.
22. Add the cream and bring to a boil.
23. Remove the saucepan from the heat and stir in the icing sugar.  If this step proves difficult, transfer the penuche frosting to the bowl of a stand mixer fitted with a paddle attachment and beat until well incorporated.
24. Place a cake layer on the serving platter.
25. Slather half of the penuche frosting onto the cake.
26. Place the second cake layer on top of the frosting.
27. Spread the rest of the frosting onto the cake.
28. Store in an airtight container at room temperature for up to 3 days.