In a large sauce pan, over medium heat, melt the butter. Stir in the sugar and cook for about 2 minutes, or until the sugar dissolves. Add the orange juice and orange zest and cook until the syrup thickens slightly, 2 to 3 minutes. Add the cherries and cook until they are tender, 2 to 3 minutes longer. 

In a small cup, stir the cornstarch and water together to form a slurry. Stir the slurry into the cherry mixture and cook until the sauce thickens enough to coat the back of a spoon, 2 to 3 minutes. 

Pour the brandy over the cherries. Place the pan back on the heat and carefully shake the pan several times to ignite the pan. If the pan does not light use a match to flame the cherries and cook until the alcohol evaporates and the sauce is thickened.

Divide the ice cream between four shallow bowls. Spoon the cherry mixture over the ice cream and serve.