First, set the Instant Pot to saute mode and add the olive oil.
Saute onions, once the oil is hot, for 5 minutes.
Add minced garlic and continue sautéing for an additional 2 minutes.
Stir in cornstarch and saute. After about 5 minutes, it will be brown and bubbly and this is what we want.
Turn off Instant Pot and add chicken broth. Scrape the bottom of the Instant Pot pan with a spatula to remove stuck-on pieces of food. Keep everything in the pot still!
Add parsley, thyme, and black pepper and mix well.
Add heavy cream, potatoes, corn, and ham. Continue stirring to make sure it is well combined.
Place lid on instant pot and seal the vent. You will want to pressure cook it for 30 minutes.
When it is done cooking, do a natural release and stir before serving. Be careful as it will be hot!