Plug in Instant Pot and press "Saute". Set it to "normal" heat for thirty minutes. You will probably only need around 15 minutes of cook time, but I don't like it when the Instant Pot turns off in the middle of cooking, so I always set it for longer than I need when I am cooking with Saute. Allow to heat until the screen displays, "Hot". Meanwhile, let's mix up the pancakes!
Measure 1.25 cups of pancake mix into a medium bowl. Set aside.
Crack an egg into a bowl. Whisk egg a bit and then stir in the milk. Pour this mixture into the bowl of pancake mix. Stir until all large lumps are gone. Don't overmix. If the batter seems a little thin, add more pancake mix (in 2 tablespoon increments).
Ladle three pancakes into the Instant Pot insert. Aim for three 3" pancakes (about 2 tablespoons of batter per pancake) per batch.
Cook pancakes until the bubbles are popping and the edges are starting to set. About 90 seconds. Flip and continue cooking until done--about 45-60 seconds. Remove from Instant Pot and repeat until you have cooked all the batter.