Step 1: Cut your beef chuck into chunks. (You don't have to do this, I have just found that it cooks a little more evenly if you do. Set your instapot to the sear option. Pour your oil in the bottom of the pot. When your oil begins to sizzle, brown your meat on both sides.
Step 2: Remove your beef roast from the instapot and add onions, broth, carrots, and any spices your would like. Put your beef roast back in the cooking pot on top of the onions.
Step 3: Lock your lid in place and set on pressure cook for 60 minutes. After done cooking turn off your pot and let sit for at least 10 minutes until doing a quick release.
Step 4: If you sauce is thin add a slurry of water and flour and stir in your pot roast.