1/2 cup chopped walnuts
2 tablespoons unsalted butter
2 Granny Smith apples, peeled, cored, cut into 1/4-inch slices
1/2 teaspoon cinnamon
1/2 teaspoon vanilla extract
1/4 cup pure maple syrup
1 pint vanilla ice cream
Place a medium skillet over medium heat. Add walnuts and cook, shaking pan often, until nuts are golden, 2 to 3 minutes. Transfer to a plate to cool.
Melt butter in same skillet over medium heat. Add apples, cinnamon and vanilla and cook, stirring frequently, until apples are soft, about 5 minutes. Stir in maple syrup and continue to cook until syrup thickens, 1 to 2 minutes longer. Transfer to a bowl and set aside for 10 minutes to cool slightly.
Divide ice cream among 4 bowls. Top with apples and sprinkle with walnuts. Serve immediately