Preheat the oven to 350° and butter a 12-inch cast-iron skillet.
In a food processor, combine the sugar with the flour, pecans and cinnamon. Add the butter and pulse until the mixture is fine. Transfer the topping to a bowl and press into clumps.
In a large bowl, combine the apples and pears with the currants, sugar, cinnamon, cardamom, honey and Cognac and stir until the sugar is dissolved. Spread the fruit in the skillet and scatter the topping over the fruit.
Bake the crisp in the center of the oven for about 1 hour, until the fruit is bubbling and the topping is browned. Let cool for 20 minutes before serving with ice cream.