In a heavy bottomed sauce pan, heat oil and once the oil starts to shimmer, add tomatoes and cook on medium flame until they start to turn slightly mushy.
Add tamarind pulp, salt, red chili powder and cook until tomatoes are completely cooked through. The mixture should be quite thick. It took about 45 minutes to get to this stage.
Add methi podi (ground fenugreek); mix well and cook for another 5 minutes.
For tempering, heat 1 tbsp peanut/ sesame oil in a small saucepan, add mustard seeds and chopped garlic cloves and sauté until the seeds start to splutter and garlic starts to turn golden. Keep a close eye, since it doesn't too long for garlic to burn.
Pour the tempering onto the tomato mixture. Once completely cooled, transfer pachadi into a clean glass jar. I keep this in the fridge, but you can leave it on the counter for up to a month.