Cut the potatoes into 1½-inch chunks and place them in a steamer basket that fits your Instant Pot. Be sure to cut the potato chunks large enough so they don't fall through the spaces in the rack.
4 Yukon gold potatoes
Set Instant Pot to Sauté and add the bacon strips. Fry until just crispy but not so crispy they end up crunchy hard. Transfer the bacon to a paper towel-lined plate and set aside.
8 slices bacon
Add the diced onion to the pot and cook the onion until translucent, about 2-3 minutes - stirring occasionally.
1 large sweet yellow onion
Add the garlic and sausage to the pot and cook until sausage is cooked through and no longer pink in the middle, about 5 minutes. Stir often.
2 cloves garlic, 1 lb. bulk sweet Italian sausage
Transfer the sausage/onion/garlic mixture to a second paper towel-lined plate. Set aside.
Pour the bacon/sausage fat into a heatproof bowl, and keep it in a sealed container, in the fridge for later use.
Place the Instant Pot insert pot back in the Instant Pot with the setting still set to Sauté.
To deglaze the pan, slowly pour 2 cups chicken stock into the pot, while scraping the bottom of the pot with a wooden spatula. Once the pan is deglazed, add the red pepper flakes, kosher salt, black pepper and stir.
4 cups chicken broth, ⅛ tsp crushed red pepper flakes, ½ tsp kosher salt, ½ tsp freshly ground black pepper
Turn off the Instant Pot.
Set the steamer basket, with the prepared potatoes, in the Instant Pot and lock down the lid. Set the Pot to manual and pressure-cook the potatoes on HIGH for 4 minutes. When cooking time is done, cover the release valve with a kitchen cloth and use the quick pressure release.
When the pressure valve drops, carefully remove the lid and the potatoes from the pot. The potatoes should be 'almost' fork-tender or fork-tender but NOT falling apart.
Add the remaining 2 cups chicken stock to the liquid in the pot and set the Instant Pot to Simmer/Sauté.
In a small bowl, combine 3 tbsp cornstarch and ½ cup heavy cream, and add the mixture to the liquid in the pot. Bring the mixture to a boil, stirring often until smooth, and the soup thickens a bit.
3 tbsp cornstarch, 1½ cups heavy cream
After the soup thickens, add the remaining 1-cup heavy cream, half the crispy bacon lardons, the onion/garlic/sausage mixture, potatoes, wine and the spinach. Mix well. Simmer, stirring often, until the soup is the desired consistency (and the potatoes are fork-tender).
¼ cup dry or semi-dry white wine, 2 cups fresh baby spinach leaves
Serve with a topping of crispy bacon lardons and a sprinkling of grated Parmesan and chopped parsley with a side of crusty bread (if desired). Enjoy!
freshly grated Parmesan or Parmigiano Reggiano cheese, crusty bread, fresh parsley