Soak the green mung beans and black chickpeas separately with sufficient water for 6 to 8 hours. Overnight soaking is fine too. Then drain the water, spread the soaked lentils on a cloth, and let it rest for 2 hours—no need to keep it under the sun. The green mung beans and chickpeas should be moist but not wet.
Roasting the ingredients:
Heat a heavy-bottomed kadai or pan and start roasting the ingredients one by one without any oil. I first started with dry coconut pieces. Roast the coconut pieces until they turn lightly golden brown and crisp over medium-low heat. It usually takes about 5 to 7 minutes. Remove the roasted coconut and set it aside on a plate or bowl.
Next, add the black chickpeas to the same pan. Roast the chickpeas until they are dry and crisp. It will start to pop and split like below. It took me 25 minutes to roast the chickpeas. I would recommend tasting the chickpeas. If it has reached the desired crisp texture, stop roasting. Now remove the roasted chickpeas and set them aside in a bowl. (do not mix it now with roasted coconut)
Next, add the green mung beans to the same pan. Like chickpeas, roast the green mung beans until they are dry and crisp. It took me 15 minutes to roast the green mung beans. Taste the beans and if it has reached the desired crip texture, stop roasting. Remove the roasted mung beans and set them aside in the same bowl as black chickpeas. You can mix the green mung beans and chickpeas.
In the same kadai, add the peanuts and roast for 3 to 4 minutes until the skin turns light brown. Remove the peanuts and set them aside.
In the same kadai, add the roasted gram and roast for two minutes, and turn off the heat. Let it stay in the kadai for a couple of minutes so that it becomes crisp in the residual heat. But keep an eye on them.
Here are the roasted ingredients. Let them cool down completely.
Preparing the spice paste:
Combine the red chili powder, salt, ground turmeric, asafoetida, and water. Make a paste. Now add this paste to the roasted green mung beans and black chickpeas mixture. Mix well and make sure the spice paste is evenly coated.
Roasting the lentils again
Heat a pan and add the spice-coated lentil/legume mix. Dry roast until the mixture is dehydrated. The moisture from the spice mix should be gone. Keep on medium flame and fry till the lentils get dried, and it took me about 15 minutes.
Turn off the heat and add the roasted coconut, peanuts, and roasted gram. Mix well and let it cool. Store in an air-tight container.
Notes
The cooking time depends upon the pan and the heat setting. Keep an eye on the lentils/legumes, and don't leave them unattended. Also, do not roast them at high heat. I recommend medium to medium-low heat.
Adjust the salt and spices as per your taste preference. This trail mix is slightly on the spicy side.
You might have to roast a little longer if you add more water while making the spice paste. I have made that mistake a couple of times. For this measure, 1.5 tbsp water is sufficient. But I did add 2 tbsp of water.
You can add more lentils and legumes like moth beans, black-eyed peas, horse gram, etc. You have to roast them one by one. When you add more lentils and legumes, make sure to adjust the salt and spice accordingly.
I usually don't remove the peanut skin. You can also use skinned peanuts or remove the skin after roasting.
Fresh or frozen coconut doesn't work in this recipe. So make sure to dry kobbari, and you can readily find them in Indian groceries.