SET the puff pastry out on the counter to thaw for 30 minutes.
PREHEAT your oven to 400 degrees.
TURN on the Sauté function. Once hot, add 1 tablespoon oil followed by the sausage. Cook, stirring once or twice, for about 2 minutes, or until browned on at least one side.
REMOVE the sausage and set aside. Add 2 teaspoons oil as needed. Add the onion and shallots and sauté for 2 minutes, scraping the bottom of the pot. Add the carrots and garlic and sauté for 1 minute more. Turn off the Sauté function. Add the potatoes, browned sausage, and broth. Season with salt and pepper and secure the lid.
COOK at high pressure for 7 minutes and use a natural release for 10 minutes followed by a quick release.
MEANWHILE, once the oven has preheated and the puff pastry is thawed, cut the sheet into four rectangles. Space 1 inch apart on a baking sheet. Bake for 10 to 20 minutes, following package directions, until nicely browned and flaky.
ONCE the pressure has released, turn on the Sauté function. Carefully remove and dispose of 1/2 cup of the broth, avoiding the onions when possible. Create a paste out of the butter and the flour and add to the pot. Stir and cook for about 3 minutes, until the mixture begins to thicken up. Taste for seasoning. Turn off the Sauté function and let cool for 5 to 10 minutes.
ADD the pot pie mixture to 4 bowls or soup plates and serve topped with the baked puff pastry.
P.S. Swap out some of the potatoes for parsnips or butternut squash, or add a big handful of frozen peas at the end.