Place the flour and sugar in a large bowl and mix well. Taking a few cubes of butter at a time rub into the flour mixture. Keep rubbing until the mixture resembles breadcrumbs.
Add the cinnamon and oats.
Peel, core and chop pears. Place pears in a medium-sized ovenproof dish and scatter the fudge pieces.
Sprinkle the flour mixture over the fruit and fudge.
Bake in the oven for 25-30 minutes until the crumble is browned and the fruit mixture bubbling.