Apple Walnut Topping

1. Peel, core, and cut apples into eighths.
2. In either a well-seasoned 10” cast-iron skillet or a 10” non-stick skillet, melt butter over medium low heat until just melted (butter should not separate).
3. Stir in sugar until combined.
4. Arrange apple pieces in skillet and sprinkle evenly with walnuts.
5. Raise the heat to medium.
6. Cook mixture, undisturbed, 25 to 35 minutes, or until apples are tender and sugar is a golden caramel.
7. Remove from heat and reserve.

Cake Batter

1. Preheat oven to 375° F.
2. Make the muffin batter according to manufacturer’s instructions while the Apple Walnut Topping is caramelizing.
3. Fold in chopped apple, cinnamon and ginger.
4. Spoon batter evenly over topping.
5. With a metal spatula, spread butter, being careful not to disturb topping, leaving a ¼” border of topping uncovered.
6. Place skillet in a shallow baking pan and bake in middle oven rack for 35 to 40 minutes, or until a tester comes out with crumbs adhering and cake is golden brown.
7. Cool cake in skillet on a rack for 10 minutes.
8. Run a thin knife around edge of skillet and carefully invert cake onto a plate.
9. Serve cake warm or at room temperature with extra caramel sauce, whipped cream or a sprinkle of powdered sugar.