Bring the chuck roast to room temperature and season it well with salt and pepper.
Heat the Instant Pot using the sauté setting. Once hot, add 2 tablespoons of olive oil, then sear the roast on both sides until browned. Set aside.
Add 1 chopped onion and 3 chopped celery stalks to the pot. Cook for 2 minutes until soft and translucent. Then add 2 tablespoons of minced garlic, 8 thyme sprigs, 1 rosemary sprig, and 1 bay leaf. Cook for another minute.
Pour in 1 cup of red wine to deglaze the pot, scraping up all the browned bits. Let the wine simmer for at least 2 minutes.
Return the roast to the pot and add 2 cups of beef broth. It is best if the roast is not completely submerged, so pour in a little less broth if necessary. Lock the lid and cook on high pressure for 75 minutes.
Once the cooking time is complete, let the pressure release naturally (about 30 minutes). Carefully remove the roast, cover it, and set it aside to rest.
Pour the cooking liquid into a separate container using a fine mesh strainer, then return it to the pot. Discard the aromatics.
Add 1 sliced onion, 1 lb. peeled and chunked carrots, and 1 lb. peeled and roughly chopped potatoes to the pot. In a small dish, combine 2 Tbsp. cornstarch with ¼ cup water to make a slurry. Add it to the pot along with one teaspoon of salt.
Lock the lid and cook on high pressure for 4 minutes, then quick-release the pressure. Using two forks, pull apart the roast. Add it back to the pot with the gravy and vegetables.