Add olive oil to Instant Pot inner cooking pot and select the “Sauté’ function. Use the “Adjust” button to select the “Normal” (medium) setting.
Once hot, add the diced onion and ground sirloin. Add the Italian seasoning and season with salt and black pepper, to taste. Stir to combine and cook, stirring frequently, until the onion develops some color and the beef is mostly browned, approximately 6-7 minutes.
Push the “Keep Warm/Cancel” button and add the red potatoes and beef broth. Add lid and lock into place. Switch the vent to “Sealing” and select the “Manual” setting on “High.” Adjust cook time to 3 minutes.
When cook time is complete, allow the pressure to release naturally for 10 minutes, then do a quick release for any remaining steam before carefully removing the lid.
To prevent curdling, temper the heavy cream by adding 2-3 tablespoons of the hot liquid from inside the Instant Pot to it before adding it to the container. Stir to combine.
Add the cheddar cheese, one cup at a time, and stir until completely melted. Serve immediately with some freshly chopped parsley and a sprinkle of smoked paprika for garnish, if desired. Enjoy!