Heat instant pot on saute, and select "more". Add oil and let it get hot.
Add the mustard seeds and let them start to change color and pop. Add in the curry leaves, garlic, green chile and asafetida if using. Mix well and cook for half to 1 minute, stirring frequently.
Add turmeric and mix in. Switch off saute.
Add cabbage and salt and mix well. Add water and mix well. (you can add in 2 tbsp fresh or shredded coconut, cayenne for extra heat )
Close lid and pressure cook on low pressure or 3 mins (4 mins if the cabbage wasnt finely chopped or has hardy leaves). Let the pot sit for 5 mins then quick release.
Mix in the peas and let sit for a minute. Garnish with cilantro and pepper flakes and some lemon juice if you like and serve with dals and flatbread or rice.
Variations: Use 1 tsp cumin seeds and 1/2 tsp garam masala as the spicesAdd in 2 tbsp coconut and 1 tsp ground coriander or sambhar masala for variation. Asafetida is often mixed with wheat flours or starches while grinding, so it might not be gluten-free. For gluten-free asafetida, make sure to get one with rice flour or starch. It is optional in the recipe.Stovetop:
Follow Steps 1 to 3 over medium high heat in a skillet. Reduce heat to medium. Add the cabbage, salt and water, cover and cook for 5 mins, stir, add more water to deglaze if needed, then, cover, reduce heat to low and continue to cook for 8 to 10 mins or until cabbage is cooked to preference. Add in the peas and cook for another 2-3 mins. Garnish and serve.