Take 400 grams or 2 raw mangoes. Peel the skin and cut them into medium-sized pieces.
You will get about 2 cups of mango pieces. Transfer them to a bowl and add ½ tsp turmeric powder, 1 tbsp red chilli powder, 1 tbsp coriander powder, ½ tsp garam masala, salt to taste, and 1 tbsp oil. Mix well so that the masala coats the mango pieces evenly.
Now heat 4 tbsp oil in a pan. Add ½ tsp mustard seeds, 1 tsp cumin seeds, 1 tsp white sesame seeds, 1 tsp fennel seeds, a pinch of hing, some curry leaves, and 2 dry red chillies. Sauté for a few seconds until aromatic.
Then add the mango pieces and sauté for 1–2 minutes.
Lower the flame, cover the sabji with a plate (thali), and add some water on top of the plate. Cook on low flame for 3–4 minutes.
Now add about ¼ cup hot water, mix well, cover again, and cook until the mango pieces become soft.
Add 1 cup jaggery and mix well.
Cook on low flame for 2–3 minutes until the jaggery melts and gets absorbed into the mango pieces, making them slightly transparent.
Kachi Keri nu Shak is ready. Serve immediately or store it in an airtight container. It stays fresh for up to 1 week in the refrigerator.