Preheat the oven to 200°C.
Place the gooseberries, sugar, lemon juice and cinnamon in an ovenproof dish.
In a large bowl, rub together the sugar, ground almonds and flour until you have a mixture resembling fine breadcrumbs. Set aside.
Dice the butter and rub into the flour and sugar mixture until it resembles coarse and chunky breadcrumbs.
Add the flaked almonds, hazelnuts and nutmeg and mix together. Cover the gooseberries with the crumble mixture.
Place in the oven for approximately 20 minutes. The crumble should be golden brown and the filling should be bubbling when ready.
Serve with custard or whipped cream.