Using the Sauté function on the Instant Pot, melt the butter right in the pot.
Then sauté the onion in the butter, 'til it starts to soften.
Stir the ground beef in with the onion, cooking 'til the meat is browned.
Add in the chili beans, diced tomatoes, tomato sauce, molasses, and chili powder, stirring everything together.
Put the cover on your Instant Pot, seal the vent, and set it to cook for about 10 minutes.
Once it's cooked, let it naturally release pressure.
Serve with sour cream, shredded cheese, and whatever else your heart desires.