Sprinkle 1 tablespoon sugar into a pot that will fit inside your Instant Pot, and place over direct heat until the sugar is melted and browned. Be careful not to burn it.
In a blender, mix together all remaining ingredients and carefully pour on top of the caramelized sugar.
Pour one cup of water in the bottom of the electric Instant Pot, put in a trivet, and place custard pot on top of it.
Cook at High Pressure for 5 minutes, let pressure release naturally.
Put the custard in the fridge to cool. Once cooled, unmold gently and serve cold, perhaps with some whipped cream for additional fat.