If you’ve ever wanted to make giardiniera at home without canning or specialty ingredients, this refrigerator version is the place to start. A hot vinegar brine, fresh vegetables, and a little patience are all it takes.
In a large bowl, add cauliflower, carrots, celery, red bell pepper, serranos, and garlic. Toss until uniformly combined.
Pack the vegetables into 4 pint jars leaving 1/2-inch of headspace.
In a large saucepan over medium-high heat, add vinegar, water, sugar, salt, and dill. Bring to a boil, then remove from heat, cover, and steep for 10 minutes.
Remove the bundle of dill and return the brine to a boil. Remove from heat. Using a ladle, divide the brine among the jars, then cover and refrigerate for 7 days.