Step 1

Heat the oil in a saucepan. Add the mustard, if using, and wait for it to sputter.

Step 2

Add the onions and curry leaves, if using, and saute on medium heat until it sotens and becomes translucent.

Step 3

Add the mushrooms and spinach and saute until the spinach wilts, which should take no more than a couple of minutes.

Step 4

Add half the coconut milk and the curry powder with half a cup of water. Stir to mix and let the sauce come to a boil.

Step 5

Add salt to taste and the remaining coconut milk. Warm the curry through at this point but turn off the heat before it comes to a boil.

Step 6

Check salt and add more if needed.