How to Make It
In a large saucepan of boiling salted water, cook the cauliflower until crisp-tender, 4 to 5 minutes. Drain the cauliflower and cool under running water. Drain again and dry on paper towels.
In a bowl, combine the shallots, vinegar and cumin. Whisk in the oil and season with salt and pepper. Add the cauliflower and peppers and toss. Transfer to a shallow dish and let marinate at room temperature for at least 2 hours, turning the vegetables in the marinade. Season with salt and pepper and serve.