Photograph: Brett Stevens
Whisk together the olive oil and vinegar with the caster sugar and season with salt and freshly ground black pepper.
Toast the hazelnuts in a nonstick frying pan over a medium-high heat for 7-8 minutes, shaking the pan to toast them evenly. Let them cool slightly and then roughly chop.
To serve, tip the salad leaves and the apple slices into a bowl. Pour over the dressing and toss together then scatter with the hazelnuts.
Kitchen secret: add some crunchy texture with this autumnal salad. Use British eating apples when they’re in season and if you have cobnuts in the garden they would make lovely substitutes for the hazelnuts.