Rinse and peel all of the vegetables. Trim and julienne the peppers. Thinly slice the zucchini. Cut the onions into thin rings. Remove the stalk from the celery and thinly slice. Chiffonade the celery leaves. Finely dice the carrots, and separate the cauliflower into florets. Thinly slice the scallions.
Add the vinegar, 1.5 liters (approximately 1.5 quarts) of water, and the salt to a saucepan. Bring to a boil, then begin to add the vegetables separately into the cooking liquid. Cook each vegetables about 3 minutes, then remove with a slotted spoon. Transfer each vegetable to an ice water bath, and drain thoroughly.
Heat the 1-2 tablespoons of oil in a pan. Cook the vegetables in batches for 2-3 minutes per batch, then remove from the pan. Coarsely grind the coriander seeds and peppercorns in a mortar. Layer the vegetables and ground spices into jars, then fill with oil. The vegetables should be completely covered. Let the vegetables infuse for at least 3 days before using.