Set your pressure cooker to sauté mode. Add the olive oil and onion, and cook for 2 to 3 minutes until softened. Add ground turkey, breaking it up with a spatula as it browns. Cook until no longer pink.
Add the green chilies, salsa, chopped tomatoes, olives, and cilantro, and stir to combine.
Remove from heat and turn off sauté mode. Remove the meat mixture from the pressure cooker.
Fill the bottom of the pressure cooker with water that’s about 1/4 inch deep. Then ladle a third of the meat and salsa mixture into the pressure cooker. Top with a layer of two corn tortillas, overlapping them (and perhaps tearing them) to fit. Repeat this for three layers, ending with a tortilla layer on top.
Seal the lid and cook on high pressure for 5 minutes. Once the time is up, quick-release the pressure.
Remove the top and sprinkle with the cheese. Recover and allow the dish to rest for around 10 minutes, so the cheese can melt.
Top with a dollop of sour cream and serve.