Take two large-sized eggplants, remove their tops, peel their skins, and cut them into rough pieces.
In a pressure cooker, add 3 tbsp of oil, the eggplant pieces, 2 medium-sized tomatoes, some coriander leaves with stems, and ½ cup of water. Cover the lid and cook until 2 whistles on high flame.
Meanwhile, in a mortar and pestle, add 12–15 garlic cloves, 1 tbsp of red chili powder, 1 tsp of cumin seeds, and a pinch of salt. Crush them to make Kathiyawadi garlic chutney. Keep it aside.
Once the pressure cooker releases its pressure naturally, take out the mixture, remove the tomato skins, and slightly mash the eggplants using a fork. Set aside some of the mixture for kacho olo.
For Kathiyawadi rigan no olo: In a kadai, heat 4 tbsp of oil. Add ½ tsp of mustard seeds, 1 tsp of cumin seeds, a pinch of asafoetida (hing), and 1 tsp of coarsely crushed coriander seeds. Sauté well.
Then, add 1 cup of chopped green onions (white part) and sauté until translucent.
Add 1 tsp of chopped ginger, 2 tbsp of chopped green garlic, and 2 chopped green chilies. Sauté well.
Next, add 4 tbsp of green tuvar dana and 4 tbsp of green peas. Sauté them.
Add 1 tbsp of Kathiyawadi garlic chutney, ½ tsp of turmeric powder, salt to taste, 1 tbsp of red chili powder, 2 tbsp of coriander powder, 1 tsp of cumin powder, 1 tsp of kitchen king masala, and some water. Sauté the masala until the oil separates from the sides.
Now, add 1 medium-sized tomato (chopped) and ¾ cup of the green part of spring onions. Sauté well.
Add the rigan olo mixture to the gravy and mix well.
Cover and cook the rigan no olo for 5–7 minutes on low flame.
Add some lemon juice and mix well.
Place a small bowl in the center of the kadai, add hot charcoal to it, and pour ghee over it. Cover the kadai for 1 minute to infuse the smoky flavor. Remove the bowl, garnish with coriander leaves, and serve the rigan no olo with bajra rotla and masala chaas.