First rinse and then chop the cauliflower to medium florets. Keep the cauliflower in warm water for 15 to 20 minutes.
Next rinse, peel and then chop the carrots and turnips in batons or sticks of 1.5 to 2 inches.
Bring 10-12 cups of water to a rolling boil in a deep pot.
Add the cauliflower florets, carrots and turnips.
Stir and blanch for 2 to 3 minutes. Drain the blanched veggies very well.

Once the vegetables are dried, then proceed to the next step. Add chopped onions, ginger and garlic in a blender or grinder jar.
Blend to a smooth paste without adding any water. Keep this ground paste aside.

In another pan, take 2 cups grated or powdered jaggery with 1 cup vinegar. You can also add jaggery as per your taste.
Keep the pan on stove top and stir so that the jaggery dissolves.

In another deep pot or pan, heat 1 cup mustard oil till it smoking point.
Add the ground onion+ginger+garlic paste. Stir and saute.
You have to saute often as the onions tend to stick to the pan. So continue stirring.
Saute till the onion become light brown. The raw aroma of onions should go completely away. Takes about 15 to 18 minutes on a low flame.

Once the onions are sauteed, add the veggies. Then add 8 tsp salt, 4 tsp garam masala powder, 6 tsp red chilli powder and 2 tsp mustard seeds.
Stir very well. Add the jaggery + vinegar solution.
Stir again. Simmer for 8 to 9 minutes on a medium flame.
Allow the pickle to cool down. Don't cover with a lid. Just place a clean kitchen towel on the pan. In a clean sterilized jar, spoon the pickle.

In a clean sterilized jar, spoon the pickle, allow the pickle to jar to sit at room temperature for 2 to 3 days. You can even keep for 4 to 5 days. If you want, you can keep the pickle in the sun also for 2 days.
Serve this sweet and sour pickle.