Lamb meat comes from the young offspring of sheep and is popular for its flavor and lean protein. Though lamb meat is more tender than other types of red meat, a shoulder steak can take some time to cook and soften. Using a pressure cooker is a efficient way to make a savory lamb shoulder steak. Unlike microwaves, a pressure cooker seals in the juices that flavor the meat, rather than drying it out; unlike boiling, baking and other methods of cooking, it will preserve more of the meat's natural nutrients. Cooking a lamb steak in a pressure cooker takes far less time than in a slow cooker.
Defrost the lamb shoulder steak by placing it in the refrigerator for 2 to 4 hours. Heat the vegetable oil in the pressure cooker on medium-high heat. Brown the lamb steak lightly in the oil without putting the lid on the cooker. Remove the lamb from the cooker and put aside on a plate.
Add the chopped onion and garlic to the remaining oil in the cooker and cook until they are lightly browned and transparent. Add the remaining ingredients, except for the chicken or vegetable stock and the cornstarch. Stir the ingredients together to make an even mixture.
Return the lamb shoulder steak to the pressure cooker and coat it with the other ingredients in the pot. Let the steak cook for 1 minute before pouring the broth into the cooker. Place the lid on the pressure cooker and seal it tightly. Reduce the burner heat to low and cook for 9 minutes with the lid on.
Remove the pressure cooker from the stove and immediately place under cold running water in your sink to reduce the pressure inside quickly. You should see steam escaping from the valve in the lid. Leave the lid on the cooker and the valve in place until all the steam is released.
Dilute the cornstarch in a tablespoon of water and mix it until it is smooth in consistency. Remove the lid on the pressure cooker and put the pot back onto the low heat. Place the steak in a serving dish, leaving behind the liquid and other ingredients in the cooker. Add the diluted cornstarch to the remaining liquid in the pot. Continue cooking, stirring until it has thickened, making gravy for the steak. Pour over the lamb shoulder steak and serve immediately.