Divide the cauliflower into small florets and remove the stems. Cook in salted boiling water for 3-5 minutes. Quench and drain well. Put in a bowl with oil and vinegar and season with salt and pepper. Pluck the oregano leaves from the steep sides and add to the cauliflower with the rinsed capers and the olives cut into rings. Cut the peppers into fine strips, add to the cauliflower and mix everything thoroughly.
Let the salad steep for at least 3 hours at room temperature before serving.