Season both sides of the chicken thighs with salt, pepper, and thyme (about 1/2 teaspoon thyme per side).
Set the Instant Pot to SAUTE and melt the butter. Sear the chicken 3-4 minutes per side until browned, then remove and set aside.
Add the carrots, celery, and onion. Saute about 2 minutes, stirring to coat in the butter and seasonings.
Pour in 2 cups cold water, then add the garlic powder, salt, and pepper. Place the browned chicken back on top of the veggies.
Close the lid, set to HIGH PRESSURE for 6 minutes, and make sure the valve is sealing.
When the timer goes off, quick release the pressure. Once fully released, open the lid and move the chicken to a cutting board.
Add 4 cups chicken broth and 2 cups water. Set to SAUTE and bring to a boil, then stir in the Better Than Bouillon.
Add the egg noodles and cook according to package directions (see notes for a faster method). Meanwhile, shred or chop the chicken and stir it back in.
Taste and adjust seasoning with more salt and pepper if needed. Serve hot and enjoy!