Combine 1 cup (250 mL) of the Cheddar with cream cheese, sour cream and Worcestershire in a food processor. Add salt and pepper, process until smooth and transfer to a bowl.
Toss diced apple in lemon juice. Using a spatula, mix into cheese spread along with parsley and remaining cheddar. Taste and adjust seasoning, if necessary. Garnish with celery leaves, if desired. Serve immediately with celery sticks, or cover with plastic wrap and refrigerate until needed.
This delicious cheesy spread is super-versatile: Spread it on celery sticks or crostini or bake it in the over and serve with crackers.