Prep the Vegetables: Break the cauliflower into small florets, no larger than ¾-inch. Trim the radishes and peel the carrots.
Using a mandolin or a sharp knife, slice the radishes and carrots very thinly.
Place all prepared vegetables into a large bowl and set aside.
Temper the Spices: Pour the oil into a casserole dish or pot large enough to hold all the vegetables and place it over medium heat.
When the oil is hot, add the mustard seeds. Wait for them to pop, then add the broken Kashmiri chiles and stir-fry for one minute until fragrant.
Create the Brine: Stir in the ground turmeric and ground red chile. Immediately turn the heat down to low and carefully pour in the vinegar to avoid splattering.
Reduce the Liquid: Bring the mixture to a simmer and cook for 10 to 15 minutes over medium-low heat. The liquid should reduce and thicken to a consistency similar to a balsamic glaze.
Combine and Pickle: Add the salt and sugar to the pot, stirring until fully dissolved.
Add the bowl of sliced vegetables and stir thoroughly to coat everything in the hot brine. Immediately take the pot off the heat to keep the vegetables crisp.
Jar and Store: Carefully transfer the pickle into a large, sterilized 32-ounce jar. Press down gently to ensure all the vegetables are completely submerged in the pickling liquid. Seal the jar and allow it to cool before storing it in the refrigerator for up to one month.
While delicious immediately, the pickle's flavor deepens and improves after a day or two in the fridge.
Let the flavors meld for the best taste experience!