Traditional porcupine meatballs recipe prepared in a pressure cooker

My mum's pressure cooked porcupine meatballs were the ultimate special treat comfort food in my home growing up. They have such a unique smell and mouthfeel. While it was tomato-based, it was also very savory and the sauce looked a little more like a brown sauce than tomato sauce.

She owned the same pressure cooker I own now, pictured below. It's pretty old. I have no clue what year it's from. She's an old stovetop model and I feel like I need to give her a go. The seals and the gaskets seem like they're fine and without a nick. Wish me luck. I think I'll try making a batch this weekend in lieu of watching the royal festivities.

Here's a legit old school recipe for it--not pressure cooked--that I discovered online and thought I would share with you, too: