To prepare the parsley, remove the large stems. Don't worry so much about the small stems. Once the big stems are removed you should be left with about 6 cups of lightly packed parsley.
Chop the parsley and set aside.
Add diced cucumber, tomato and onion to a large mixing bowl.
Then add the parsley, lemon juice, olive oil and salt and pepper to the bowl.
Toss until everything is well combined.
Serve immediately or transfer to an airtight container and store in the refrigerator for up to 4 days.
