Brown-Sugar Spice Cake with Cream and Caramelized Apples

• Put oven rack in middle position and preheat oven to 350°F. Lightly butter and flour cake pan, knocking out excess flour.

Make caramelized apples:

• Peel and core apples, then cut into 1/2-inch-thick wedges.
• Spread softened butter in an even layer over bottom of a 12-inch heavy skillet and sprinkle with brown sugar. Add apple wedges and cook over moderate heat, without stirring, until sugar is melted and apples start to give off liquid, about 10 minutes. Cook, stirring occasionally, until apples are just tender and juices become syrupy, about 30 minutes more.
• Pour syrup from skillet into a small heatproof bowl, then sauté apples, stirring occasionally, until caramelized and very tender, about 30 minutes more. Return syrup to apples and cook until heated through, about 2 minutes.

Make cake while apples cook:

• Whisk together flour, baking powder, baking soda, salt, and spices in a bowl.
• Beat together butter and brown sugar in a large bowl with an electric mixer at medium speed until pale and fluffy. Beat in egg until combined. Add maple syrup, sour cream, and vanilla and beat until combined well. Reduce speed to low and add flour mixture, then mix until just incorporated.
• Spread batter in cake pan and bake until cake is golden brown and a wooden pick or skewer inserted in center comes out clean, 35 to 40 minutes. Cool in pan on a rack 10 minutes.

Make cream just before serving:

• Beat cream with sour cream and sugar using cleaned beaters at high speed until it just holds soft peaks.

To serve:

• Run a thin knife around edge of pan, then invert cake onto a plate and cut into squares. Serve warm or at room temperature, topped with warm apple mixture and cream.