Place the trivet into the Instant Pot bowl, and add 1 cup of water.
Place peach slices in a bowl with the sugar for the filling [Note 1] and set aside.
Melt the butter and place in a 6 inch baking dish or pie dish [Note 2, Note 3].
Mix the flour, sugar for the batter and the baking powder together with the milk into a thick batter.
Pour the batter on top of the butter, then place the peach filling on top including any juices. Sprinkle some ground cinnamon on top of the peach slices.
Cover and seal the baking dish with kitchen foil.
Carefully place the baking dish onto the trivet inside the Instant Pot, and place the lid on top with the valve set to sealing.
Pressure cook the peach cobber for 35 minutes on HIGH, then allow it to naturally release for 10 minutes.
Manually release the remaining pressure. Then carefully remove the peach cobber dish from the Instant Pot (use oven mitts).
Optional step: To crisp up the top of the cobbler, place it under a hot broiler for 5-10 minutes until it is browned to your liking.
Serve topped with a big scoop of vanilla ice cream. Enjoy!
Notes
If using canned peaches in syrup you can skip the additional sugar.
Use a baking dish with a capacity of ~4 cups.
If using a microwaveable baking dish, place the butter straight into it and use the microwave to melt it - approx 30 seconds.