Ingredients
For the Topping¼ cup unsalted butter, melted
½ cup sugar
2 teaspoons ground cinnamon
½ cup sugar
2 teaspoons ground cinnamon
For the Cake
¾ cup whole milk
½ cup plus 2 tablespoons unsalted butter, melted and cooled
2 large eggs, at room temperature
1 teaspoon vanilla extract
1¼ cups sugar
1½ teaspoons baking powder
1 teaspoon fine sea or table salt
1 teaspoon grated fresh nutmeg
2½ cups all-purpose flour
¾ cup thick berry jam (such as blackberry, blueberry, raspberry or four fruit)
½ cup plus 2 tablespoons unsalted butter, melted and cooled
2 large eggs, at room temperature
1 teaspoon vanilla extract
1¼ cups sugar
1½ teaspoons baking powder
1 teaspoon fine sea or table salt
1 teaspoon grated fresh nutmeg
2½ cups all-purpose flour
¾ cup thick berry jam (such as blackberry, blueberry, raspberry or four fruit)
Preparation
Heat oven to 350 degrees. Using some of the melted butter for the topping to generously brush the inside and sides of a Bundt pan.
Make the topping: In a small bowl, whisk together the sugar and cinnamon. Use about a third of the cinnamon sugar to generously coat the inside of the buttered pan, reserving the rest of the melted butter and cinnamon sugar for finishing the cake.
Make the cake: In a large bowl, whisk together the whole milk, melted and cooled butter, eggs and vanilla extract until well combined. Whisk in sugar, baking powder, fine sea salt and nutmeg until smooth. Finally, whisk in the flour until just combined.
Use a spatula to scoop half of the batter into the buttered and sugared pan. Use a spoon to create an indent or hollow in the middle of the ring of batter. Spoon the jam into the hollow (there should be batter on both sides of the jam), making sure none of the jam touches the sides of the pan. (The cake may stick otherwise.) Spoon the remaining batter on top to cover the jam.
Bake for 40 to 50 minutes, until the top is golden brown and springs back when lightly pressed. A cake tester should come out without any wet batter clinging to it. (There may be crumbs and jam adhering to the tester, and that’s fine.) Let cake cool in the pan on a rack for 10 minutes. Use a knife or offset spatula to loosen the cake from the pan and carefully flip upside down on a rack.
Brush the warm cake with the remaining melted butter and generously dust with more of the cinnamon sugar. Let cool for at least 2 hours before serving.
Make the topping: In a small bowl, whisk together the sugar and cinnamon. Use about a third of the cinnamon sugar to generously coat the inside of the buttered pan, reserving the rest of the melted butter and cinnamon sugar for finishing the cake.
Make the cake: In a large bowl, whisk together the whole milk, melted and cooled butter, eggs and vanilla extract until well combined. Whisk in sugar, baking powder, fine sea salt and nutmeg until smooth. Finally, whisk in the flour until just combined.
Use a spatula to scoop half of the batter into the buttered and sugared pan. Use a spoon to create an indent or hollow in the middle of the ring of batter. Spoon the jam into the hollow (there should be batter on both sides of the jam), making sure none of the jam touches the sides of the pan. (The cake may stick otherwise.) Spoon the remaining batter on top to cover the jam.
Bake for 40 to 50 minutes, until the top is golden brown and springs back when lightly pressed. A cake tester should come out without any wet batter clinging to it. (There may be crumbs and jam adhering to the tester, and that’s fine.) Let cake cool in the pan on a rack for 10 minutes. Use a knife or offset spatula to loosen the cake from the pan and carefully flip upside down on a rack.
Brush the warm cake with the remaining melted butter and generously dust with more of the cinnamon sugar. Let cool for at least 2 hours before serving.
(from ny times)

