Finely shred the cabbage and place in a bowl. Cut off the tips of the carrot. Peel and discard its outer skin and grate it using a box grater. Place in the bowl.
Cut off the stem and bottom of the tomato and cut in half. Then cut each half into thin slices. Place in the bowl as well.
Cut the onion and bell pepper into thin slices as well and place in the bowl with the remaining ingredients.
Add the dried oregano and season with kosher salt and freshly ground pepper.
Drizzle the olive oil and vinegar all over, and then mix the salad very well for 1-2 minutes with your hands. Rub and massage the cabbage to soften it and help the flavors blend together.
Let the salad sit in the fridge for about 1 hour to marinade, before serving.
Notes
This salad is best when left to marinate to enhance the flavors.