Ajwain or carom seeds are traditionally used in making Punjabi samosas; they have a strong flavor which is somewhat of an acquired taste. In Bengal they use nigella seeds instead and I like them much more. The wrap is much flakier and tastier when you use ghee. If you'd prefer not to make the spice blend, you can substitute 1 tablespoon curry powder plus 2 teaspoons amchur powder (raw mango powder) as a shortcut. To substitute it when making the filling, add the peas and curry powder and cook until the raw smell of the curry dissipates, about 3 minutes. Add the potatoes, amchur and salt and cook until the mixture is well mixed and seasoned, about 2 minutes, then proceed with the recipe. The addition of peanuts gives the samosas a really nice crunch. Again, they are very prevalent in Bengali samosas and I would highly recommend them. It’s important to use a wet block of the seedless tamarind pulp and not tamarind paste for this recipe. Most of the brands are not 100% seedless and often have a skin, hence it is best to strain the mixture. Traditionally this chutney is made with jaggery, an unrefined sugar. If you can only find jaggery blocks and not powdered jaggery, it should be finely chopped.