Heat oven to 350°F. Cut pound cake into ½-inch cubes. Toast in oven on a baking sheet, turning once, until just golden around the edges, about 15 min.

Line another baking sheet with parchment; set aside. In a pot over medium-high heat, combine sugar, water and unsalted butter to make caramel. Stir until sugar dissolves and mixture reaches a boil. (Brush inside of pot with a wet pastry brush to remove stray sugar crystals.) Boil gently without stirring until caramel is medium amber, about 8 minutes.

Remove from heat and immediately add cake cubes to pot; stir very gently to coat. Quickly pour cubes on parchment and separate. I use two forks or spatulas to separate them. Let cool.