Lightly grease a round 7 inch cake pan with butter or oil. Cover the bottom of the pan with aluminum foil to avoid any liquid from dripping out.
In a large bowl, whisk eggs, milk, brown sugar, marmalade, vanilla and 1 tsp ground cinnamon until smooth. Note: I have also tried orange zest (from 1 orange) mixed with 1 tablespoon of honey instead of marmalade and it adds a great refreshing flavor.
Add bread cubes to the bowl and mix gently, so that all the bread pieces are covered with liquids.
Line up the bread pieces in the cake pan
Cover the pan with a paper towel and then an aluminum foil on top. If you prefer to not use aluminum foil, cover the pan with a few paper towels instead. This prevents from any additional water from getting into the pan.
Add 1 cup of water in the Instant Pot. Place the cake pan on the trivet.
Gently put the trivet in the pot. Close Instant Pot lid with pressure valve to sealing.
Pressure Cook for 15 mins and allow 10 minutes natural pressure release.
Open the Instant Pot and using silicon mitts carefully take out the trivet along with the cake pan.
Allow to sit for 5 mins. You can also broil for 5 mins for crispy top
Sprinkle more cinnamon and spread a tablespoon of butter cut into smaller pieces (love salted butter)
Drizzle some maple syrup and add your favorite toppings - fruit, nuts, raisins or chocolate chips