Sprinkle garlic salt as desired on both sides of chuck roast. In Instant Pot (6 Quart) on saute setting, sear each side of roast. You can also do this in a skillet on medium high heat then transfer to slow cooker.
In IP or slow cooker, pour in the can of chipotle peppers in adobo sauce on top of roast. (If you prefer a smooth sauce, pour can of peppers into blender or food processor and pulse until smooth before pouring on roast)
Next, pour 1 cup of beef stock or broth around roast. Toss in bay leaves. Lock IP and set to Pressure Cook on High for 70 minutes, let pressure release. For slow cooker, set on low for 8 hours or 6 hours on high.
Once done, shred with two forks and serve with hard or soft tortillas with desired toppings.