Preheat the oven to 400°F (200°C) and roll out the puff pastry on a floured surface until smooth.

Spread a thin layer of Dijon mustard on the puff pastry, then layer the sliced ham and shredded cheddar cheese.

Roll the pastry tightly into a log shape, wrap in plastic wrap, and chill for at least 30 minutes.

Slice the chilled log into ½-inch thick rounds.

Arrange the pinwheels on a baking sheet and bake for 20-25 minutes until golden brown.

Let cool slightly and serve warm on a platter.