Mushroom - Cooking like a Boss

Quantity recently doubled to reflect the lack of wartime rationing! Tom may not like the concept of mushrooms.

28g 0.028kg 0.062lb 0.988oz margarine for onion	melt	cook til soft and translucent	sweat 8 minutes	simmer 1hr with lid	blend until conceptually smooth
1 onion	chopped
340g 0.34kg 0.75lb 12oz button mushrooms	wash and quater
47g 0.047kg 0.104lb 1.66oz margarine for mushrooms
1tsp 0.005l 5ml ¹⁄₃tbsp 0.021cup 0.009pint parsley
1l 1000ml 66 ²⁄₃tbsp 200tsp 4.23cup 1.76pint chicken stock