Cut your cabbage into pieces, and place in batches in your food processor fitted with the s blade or coarse shredding disc, and pulse quickly just a few times, until roughly chopped. Don't process too much or your cabbage will be like rice. 

Toss the cabbage, parsley, and green onions with the olive oil, lemon juice, salt, and pepper. Tweak oil, lemon juice, salt, and pepper to taste.