Chop the veggies and chillies into little pieces or julienne strips, whatever you prefer
Soak the veggies together with the green chillies and garlic in 2 cups vinegar and 1 teaspoon salt. Ensure it is a sterilized bottle. Vegetable must be soaked for 2 days
After 2 days drain the vinegar and pat the veggies dry with some clean paper towels
Roast the coriander seeds, nigella seeds, fenugreek seeds and mustard seeds on a low heat until fragrant. Do not let the spices burn. Use a pestle and mortar or coffee grinder and grind the spices, should be coarsley ground, not fine
Add 1/4 cup oil and the coarsley ground spices together with the chilli flakes, turmeric, black peppercorn, cloves, cinnamon stick to stovetop and heat on low heat just until oil is warm. Do not let it boil or heat up too much, especially if using olive oil
Mix the oil spice mixture into the veggies. Add the sugar, you can add less or more according to your taste
Transfer the pickle to a sterilized bottle and store in the refrigerator