Set Instant Pot to sauté. Add oil and swirl to coat the bottom, then add sausage in an even layer (working in batches if necessary) and cook until browned, turning halfway through cook time, 3-4 minutes.

Meanwhile, trim leeks, and slice in half lengthwise, then crosswise into thin half moons. When the sausage is done, add to the pot insert, along with onion and garlic. Cook, stirring often, until softened, about 5 minutes more.

Add bell pepper, potatoes, and smoked paprika, along with salt and pepper. Stir to combine everything, then add broth, scraping the browned bits off the bottom of the pot as you stir.

Lock the lid on the Instant Pot and set to pressure cook on high. Cook for 8 minutes, then carefully release the pressure manually, following the Instant Pot instructions to do this safely.

Carefully remove the lid and add kale to the pot, then lock the lid on once more, and allow to sit for 2-3 minutes until the kale is slightly wilted.

Remove the lid, add the heavy cream, and stir once more to combine, and serve immediately. Add crushed red pepper for a spicy kick, and more salt and pepper, to taste.