For the Cake

• Neutral oil for the pan
• 6 oz peeled roasted chestnuts (1 generous cup), from a jar or bag, rinsed and patted dry
• 1/4 cup molasses (3oz/85g)
• 1/2 tsp baking soda
• 1 (15oz/425g) can unsweetened pumpkin puree (not pumpkin pie filling)
• 1 tbsp finely grated fresh ginger
• 1-1/2 tsp vanilla extract
• 2-1/2 cups all-purpose flour (11.9oz/338g)
• 2-1/4 tsp baking powder
• 1-1/2 tsp Diamond Crystal kosher salt or 3/4 teaspoon Morton kosher salt
• 1-1/2 tsp ground cinnamon
• 1/4 tsp ground nutmeg
• 1/8 tsp ground cloves
• 1-1/4 cups granulated sugar (8.8oz/250g)
• 4 large eggs (7oz/200g), at room temperature
• 2/3 cup neutral oil (5.3oz/150g), such as grapeseed or avocado

For the Toffee Sauce and Serving

• 10 tbsp unsalted butter (5oz/142g)
• 1 cup packed dark brown sugar (7.8oz/220g)
• 1 cup heavy cream (8.5oz/240g), at room temperature
• 3/4 tsp Diamond Crystal kosher salt or 1/2 teaspoon Morton kosher salt