Preheat the oven to 350 degrees F. Spray a 13- by 9-inch baking dish with nonstick cooking spray.
In a large bowl, lightly beat the eggs. Add the cream, sugar, vanilla, cinnamon, nutmeg, candied fruit mix, candied cherries and pecans, whisking to combine. Add the cubed croissants, tossing to coat. Spoon the mixture into the prepared baking dish. Let stand at room temperature for 30 minutes.
Bake until the center is set, about 1 hour. Cover with aluminum foil to prevent excess browning if necessary. Serve warm or at room temperature with Whiskey Sauce.
In a medium saucepan, combine the cream and sugar. Bring to a boil over medium heat. Reduce the heat and simmer. In a small bowl, combine the whiskey and cornstarch. Add to the simmering cream mixture. Cook until thickened, about 1 minute, stirring constantly. Remove from the heat.