The backbone of my kitchen is homemade stock. It's what makes the difference between a decent enough cook and a deadly serious one. If you're willing to take the time to make homemade stock you can seriously up your game in the kitchen.
I make two basic stocks: Chicken and Pork. Beef stock is another beast entirely. Easy enough to make in a professional kitchen but quite a difficult road to walk down in a normal home kitchen.
This formula relates to pork stock.