Sift the all-purpose flour into a bowl. Add salt and a little oil or ghee for shortening, then knead the flour with water to make a dough. Cover and let it rest for 30 minutes. Grind the moong dal into a fine paste.

Add salt, black salt, red chili powder, asafoetida, garam masala, and dried mango powder to the ground dal. Mix everything well to make the samosa filling.

After 30 minutes, divide the dough into small balls. Roll each ball into a round disc using a rolling pin. Cut the disc in half with a knife. Fold each half into a cone shape and fill with one tablespoon of the dal mixture.

In a small bowl, mix 1 tablespoon all-purpose flour with 1/2 cup water to make a paste. Apply this paste along the edges of the dough, then fold and seal the samosas. Prepare all the samosas in the same way.

Heat oil in a deep pan or wok. Once hot, reduce to medium-low heat. Add the samosas one by one and fry for 5 minutes, then turn them over. They will start to float to the top as they cook.

After another 5 minutes, turn them again. Keep turning gently until the samosas are golden brown. Remove and drain on a plate. Fry all the samosas this way. These samosas can be stored and enjoyed for up to 15 days.