Preheat oven to 180C (375F)
Salt the carcass well, drizzle with olive oil and and dust with full cream milk powder. Bake till golden.
Put the baked carcass (with any flesh still on it), the wing tips from the wings, and any wings not eaten, into an instant pot.
Add 2 crushed bay leaves, a sprig of thyme, a sprig of rosemary, to the pot.
Add any vegetables you have in your fridge that are pass their use by date.
Top up the pot to it's fill level with water,
Set on to cook under pressure for 3 hours. You may have to give it 1 hour of cooking, three times if that's the maximum time it will cook for.
Strain through a collander lined with a kitchen towel.
Now you have brown chicken stock.