Yummiest stewed lamb shank with only two ingredients

I brought my own lunch to work today and it was so good. The weird thing though is that I only used two ingredients to make it: a lamb shank and an onion. 

I put the lamb shank and the diced onion into the pressure cooker and cooked it for half an hour. Then I separate flesh from bone, remove the oils and pop it into the freezer. 

This morning, I brought it to work and placed it in the office fridge freezer. I reheated it in the microwave for 6 minutes, and it was the most delicious lunch I've had in the office in a long time. 

This made me remember one thing that Michael Pollan said in the last Coursera lecture I attended. 

He said that cooking isn't so complicated if we don't make it so. All you need to have in your home are these few basic ingredients: olive oil, onions, garlic, lemons, sugar, and salt. And as an Asian, adding soy sauce and oyster sauce would complete the list. 

All the time, I thought that the more ingredients I put in, the more complete the dish. But now I think differently. What's more important to me currently is to actually get back to cooking and so the easier and the simpler it is, the better. 

So with just some meat and an onion, how much simpler can it get. 

pearlie