Soak red chillies, turmeric powder, black peppercorns, poppy seeds, cloves, green chillies, cardamom pods, cumin seeds, fennel seeds, ginger, garlic, Coriander leaves, mint, cinnamon in vinegar and 2 tbsp of oil for 30 minutes.
Blend these soaked spices with vinegar and oil also into a fine paste.
Take your goat pieces into a bowl and add required amount of salt. Apply the blended paste to the goat pieces with fried onions and marinate for at least 2 hours or overnight.
Close the lid and select 'Manual' or 'Pressure Cook' and cook for 35-45 minutes.
I cooked the marinated lamb in an instant pot for 45 minutes but you can cook in a pan for 45 minutes or even slow cooker for 2-3 hours.
Switch off. Wait for the pressure to release, open and mix well. If you find it the consistency to be watery, open it and cook for 5-7 minutes. I did open and boiled it for 5-7 minutes over medium heat.
Garnish with coriander leaves and squeeze some lime on it.
Recipe by Relish The Bite at https://www.relishthebite.com/goat-vindaloo-in-instant-pot/