How to Make It
In a large, nonreactive saucepan, combine the red wine must with the figs, pears, apples, quince, sugar, orange zest, bay leaf and cinnamon stick. Bring to a boil over moderately high heat, stirring to dissolve the sugar.
Reduce the heat to moderate and simmer the côgnà, stirring often, until very thick and reduced to 4 cups, about 1 hour and 10 minutes. If the côgnà is not sweet enough, you can add up to another 1/2 cup of sugar. Discard the orange zest, bay leaves and cinnamon stick. Stir in the hazelnuts and simmer for 10 minutes longer. Let the côgnà cool to room temperature before serving.