Season both sides of the chicken thighs generously with salt and ground black pepper.
Turn on the Sauté mode on the Instant Pot. Once the pot is fully heated, add 1/2 tablespoon of olive oil.
Sear the chicken thighs (skin side down first) until both sides are browned.
Spoon out and discard the excess chicken fat from the Instant Pot.
Add the remaining olive oil and sauté the garlic briefly.
Add the chicken broth, heavy cream, sun-dried tomatoes, thyme, and salt. Cover the pot, select Manual, and set it to high pressure for 10 minutes.
When it beeps, turn to Quick Release. Once the valve drops, carefully remove the cover.
Switch to Sauté mode, add the grated Parmesan cheese, and cook for 2 minutes to reduce the sauce slightly.
Serve immediately.