Gooey Cinnamon Cake

Ingredients

• 2 cups all-purpose flour
• 1 teaspoon baking powder
• 1/2 teaspoon baking soda
• 1/2 teaspoon salt
• 3/4 cup butter, softened
• 1 cup granulated sugar
• 2 large eggs
• 1 teaspoon vanilla extract
• 3/4 cup buttermilk or sour cream
• 2 tablespoons ground cinnamon
• 2 cups light brown sugar, packed
• 1/2 cup butter, melted and cooled slightly

Directions

1. Fit foil into a 9- by 13-inch cake pan, with extra foil extending past all four sides. An easy way to do this is to turn the pan upside down, mold the foil around the bottom, lift it off, flip the pan upright, and nestle the shaped foil inside. Coat the foil with nonstick spray or brush it with melted butter. Set the oven to 350ºF (180ºC).
2. For the cookie base, whisk the baking powder, 1/4 teaspoon salt, and 1 1/2 cups (190g) flour together in a small bowl. In a stand mixer with the paddle attachment, or by hand, beat the 8 tablespoons (115g) butter with the 3/4 cup (150g) sugar until the mixture is pale and airy, 3 to 5 minutes.
3. Mix in the egg and the milk, pausing to scrape the bowl so everything blends evenly. Stir in the dry mixture until no floury streaks remain. Drop the batter around the prepared pan in dollops, since it is too thick to spread nicely from one big mound, then use an offset spatula to smooth it into an even layer. No need to wash the bowl; it can be used again for the next part.
4. For the soft gooey layer, whisk the corn syrup or golden syrup with the milk or cream and vanilla in a small bowl.
5. Beat the 12 tablespoons (170g) butter with the 1 cup plus 2 tablespoons (225g) sugar and salt until pale and fluffy. Add the egg and beat it in, scraping the sides of the bowl as you go.
6. Start with the flour: mix in one-third from the 1 1/4 cup (155g), then add half of the milk and corn syrup mixture. Repeat with another one-third of the flour, followed by the rest of the milk and corn syrup mixture. Finish by stirring in the remaining flour. Spoon the batter in dollops over the unbaked cookie layer, then spread it level.
7. Stir the cinnamon into the 2 tablespoons of sugar, then scatter the mixture evenly over the top of the cake.
8. Bake for 25 minutes, until the cake is gently set in the center but still feels a little damp. Take it out of the oven and cool it on a wire rack. Once cool, use the foil overhang to lift the cake from the pan, then cut it into 1-inch (3cm) squares.