Pumpkin Skillet Coffee Cake with Streusel Topping

Ingredients

• For the streusel topping:
• 1 1/2 ounces old fashioned rolled oats, not quick cooking or instant
• 1/2 ounce all-purpose or whole wheat flour
• 1/2 ounce light brown sugar
• 1 1/2 teaspoons ground cinnamon
• 1/2 teaspoon Diamond Crystal kosher salt; for table salt, use about half as much by volume or the same weight
• 1/4 teaspoon ground ginger
• 1/4 teaspoon grated nutmeg
• 1/8 teaspoon ground cloves
• 1 ounce unsalted butter, softened to about 70°F/21°C
• 2 ounces white chocolate, such as Green & Blacks, chopped into 1/4-inch pieces
• 4 ounces raw pecan pieces
• For the pumpkin skillet batter:
• 9 ounces all-purpose flour, such as Gold Medal
• 4 ounces white chocolate, such as Green & Blacks
• 1 1/2 ounces malted milk powder, such as Carnation or Hoosier Hill Farms, about 3 tablespoons; 45g
• 10 ounces light brown sugar
• 5 ounces unsalted butter, pliable but cool, about 60°F
• 1 1/2 teaspoons Diamond Crystal kosher salt; for table salt, use about half as much by volume or the same weight
• 1 teaspoon baking powder
• 1/8 teaspoon grated nutmeg
• 1/2 ounce vanilla extract
• 1 large egg, straight from the fridge
• 4 ounces pumpkin or butternut squash puree, canned or homemade

Directions

1. Make the streusel first: Add the oats, flour, brown sugar, cinnamon, salt, ginger, nutmeg, cloves and softened butter to a medium bowl, or use a stand mixer bowl if you prefer. Work the butter through the dry mixture with your hands, or use the paddle attachment, until the mixture looks pebbly and everything is evenly coated. Add the white chocolate and pecans, then keep pressing or mixing until you have a chunky crumble. Cover it and chill until you are ready for it, or pack it into a zip-top bag to freeze for as long as 3 months.
2. For the batter, pulse the flour, white chocolate and malted milk powder in a food processor until the mixture is dry and fine, with no obvious bits of white chocolate remaining. If you are not using a processor, grate the white chocolate on a Microplane, then whisk it together with the flour and malted milk powder. Put this mixture aside until you need it, or seal it in an airtight container and keep it at a cool room temperature until the date printed on the flour bag.
3. Set an oven rack in the center of the oven and heat to 350 degrees F. In a stand mixer bowl with the paddle attached, add the brown sugar, butter, salt, baking powder, nutmeg and vanilla. Start on low just to bring everything together, then switch to medium and beat until the mixture becomes pale, fluffy and very soft, about 8 minutes. Stop as needed to clean down the bowl and paddle with a flexible spatula.
4. With the mixer running on medium, add the egg and beat until the mixture is smooth. Turn the speed down to low and mix in the pumpkin purée. When that looks smooth, add the malted white chocolate-flour mixture in one addition and keep mixing until a thick batter forms. Scrape the bowl and paddle with a flexible spatula, then fold the batter a couple of times so nothing is hiding at the bottom.
5. Transfer the batter to a lightly greased cast iron skillet, using the leftover butter wrappers if you like, and smooth it into an even layer. Sprinkle the prepared streusel evenly over the surface. Bake until the cake has risen, the top is golden brown and the center is about 205 degrees F, about 35 minutes.
6. Cool the cake to room temperature before you slice it; while warm, it will seem wet and gooey because the cocoa butter in the white chocolate is still melted. Once cool, use a sharp knife to cut it into wedges, then serve it with strong coffee or tea for brunch or dessert. Wrapped individually in plastic, the pieces will keep at room temperature for several days.