For the Cake:

• 1 1/2 cups old fashioned rolled oats
• 1 1/4 cups boiling water
• 1 1/2 cups all-purpose flour
• 1 1/2 teaspoons ground cinnamon
• 1 teaspoon baking soda
• 1/2 teaspoon fine salt
• 1/4 teaspoon ground nutmeg
• 3/4 cup granulated sugar
• 3/4 cup packed light brown sugar
• 1/2 cup unsalted butter, softened
• 3 large eggs
• 1 teaspoon vanilla extract

For the topping:

• 6 tablespoons unsalted butter, melted
• 2/3 cup packed light brown sugar
• 1/4 cup milk
• 1 teaspoon vanilla extract
• 1 1/2 cups sweetened shredded coconut
• 1/2 cup chopped nuts, pecans or walnuts (optional)