1. In a medium saucepan of boiling water, blanch the cauliflower for 1 minute. Drain and let cool.
2. In one 2 1/2-quart heatproof jar or a few smaller jars, pack the cauliflower, carrots, bell pepper, chiles, garlic cloves, thyme sprigs and ginger slices, alternating them in an attractive pattern.
3. In the saucepan, combine the vinegar, allspice, sugar, salt and peppercorns and bring to a boil. Simmer over moderately high heat until the sugar dissolves. Ladle the pickling liquid into the jar. If necessary, add more vinegar to cover the vegetables. Let the pickles cool, then cover with a lid and refrigerate until very flavorful, at least 10 days.