Preheat the oven to 180°c/350°F/Gas mark 4.
Put the apple, pear, maple syrup, cinnamon, nutmeg and orange juice and zest in a saucepan. Heat over a medium heat for 5–8 minutes, or until the apples and pears have softened and the liquid has reduced.
Pulse the wholemeal/spelt flour, oats, coconut oil/butter and coconut sugar together in a food processor to form a crumble. Place the apple and pear mixture into a pie tin with tall sides. Break up the chocolate and place evenly into the mixture. Top with the crumble mixture and scatter over the chopped hazelnuts.
Bake for 25–30 minutes, until the top is slightly golden and the fruit is bubbling.