Slice the angel food cake into bite-sized cubes.
In a deep pan, heat the vegetable oil over medium heat until shimmering.
Fry the cake cubes in small batches, flipping gently, until golden brown on all sides.
Remove them carefully with a slotted spoon and drain on a paper towel.
In a large bowl, mix the sugar and cinnamon together.
While the cake bites are still warm, toss them in the cinnamon-sugar mixture until well coated.
Serve warm and devour immediately—or try not to, if you like living dangerously.