Prepare the chili peppers - Wash and completely dry the chili peppers. Make sure no traces of water exists on them. Cut the top of chilies and make small bite size pieces. I prefer to use gloves cutting and handling the peppers as the heat in peppers can give burning sensation on the fingers.
Make Dry Pickle Masala / Spice Mix - Dry roast cumin seeds, mustard seeds, coriander seeds, fenugreek seeds and fennel seeds on low flame for few minute. Stir often so not to burn the seeds. Cool the mixture completely, and blend to slightly coarse powder. Your pickle spice powder is ready.
Mix - Combine the spice powder ( pickle masala) with the cut up chilies. Also combine turmeric powder, lemon / lime juice and salt to taste. Add white vinegar. Vinegar acts as preservative and helps store the pickles for longer time.
Make Oil Tempering/ Tadka - Heat oil. Add mustard seeds, turmeric powder and a pinch of asafetida in heated oil. Let it infuse for 1 minute on medium low heat. Turn off heat. Allow the oil mixture to cool completely and pour over pickle.
Combine - Mix well to combine all the ingredients well. Let it marinate for few hours or up to couple days to soak in all the flavors.
Serve as a side dish for lunch and dinner. Or topping for toasts , pancakes etc. Store in a cool dry place or refrigerate. Enjoy !