Begin by preparing all vegetables: shred the cabbages and slice the bell pepper and onion.
Grate the carrot and halve the cherry tomatoes.
In a large mixing bowl, combine the green cabbage and red cabbage.
Add the sliced bell pepper, grated carrot, sliced onion, and halved cherry tomatoes to the bowl.
In a separate small bowl, mix the olive oil and apple cider vinegar.
Drizzle the dressing over the vegetable mixture.
Gently toss all ingredients together until well combined.
Season with salt and pepper to taste.
Add the chopped parsley and toss again.
Serve immediately or refrigerate for 30 minutes for flavors to meld.