Press sauté mode and add 1 Tbsp. olive oil or butter to the Instant Pot. Once hot, add the onions and cook until soft, about 5 minutes. Then add in the garlic, thyme, salt and pepper. (Add in celery salt and ancho chili powder here if using). Stir 1 minute.
1 Tbsp. olive oil or butter, 1 large white onion, chopped, 2-4 cloves garlic, minced, 2 sprigs thyme, fresh, chopped, 1 tsp. salt, 1/2 tsp. pepper, 1/2 tsp. celery salt* optional, 1/2 tsp. Ancho Chili Powder* optional
Add in the chicken broth and potatoes. Stir gently. Secure the lid and be sure the valve is set to sealing. Select Pressure Cook/Manual on HIGH for 8 minutes. Quick release the pressure. Once the pin drops, remove the lid.
6 large Russet potatoes, peeled and diced, 6 cups chicken broth
In a small bowl or ramekin, whisk together 2 Tbsp. milk and the cornstarch to create a slurry to thicken the soup.
1 1/2 cups milk (+ 2 Tbsp. milk, divided), 1 Tbsp. cornstarch
Set the Instant Pot back to sauté mode. Whisk in the cornstarch slurry and the 1 1/2 cups milk and the softened cream cheese. Stir. Use an immersion blender to blend until soup is smooth.
8 oz. cream cheese, softened
Season with salt and pepper to taste. Garnish with grated cheddar cheese, chopped bacon, chives, sour cream, etc. Serve warm.
The soup thickens as it sits. Store in the fridge for up to 4-5 days.