Toast the walnuts for 10 to 15 minutes in a 350°F[175°C/gas mark 4] oven, until they smell nutty and turn slightly darker. Let cool.
Peel the apples and cut them in half vertically. Cut out the cores with a paring knife or melon baller and cut the apple halves into ¼-inch [.5 cm] cubes. Don’t worry if some of the cubes are irregular; this is inevitable unless you’re going to be rigidly