Set a 6-qt Instant Pot® to the high saute setting. Add olive oil and sausage. Cook, stirring frequently, until sausage is lightly browned, about 3-5 minutes, making sure to crumble the sausage as it cooks; drain excess fat.
Add onion, and cook, stirring frequently, until translucent, about 3-4 minutes. Stir in garlic and oregano until fragrant, about 1 minute.
Stir in potatoes and chicken broth; season with salt and pepper, to taste.
Select manual setting; adjust pressure to high, and set time for 5 minutes. When finished cooking, quick-release pressure according to manufacturer's directions.
Stir in kale until wilted, about 1-2 minutes. Stir in half and half until heated through, about 1 minute; season with salt and pepper, to taste.
Serve immediately.
