Step 1: Begin by greasing a 7-inch cake pan with cooking spray. In a large mixing bowl, combine the melted butter, granulated sugar, and cocoa powder. Whisk the mixture until well blended, then incorporate the eggs and vanilla extract until the batter appears glossy. Gently mix in the flour and salt until just combined, then fold in the chocolate chips. Transfer the batter to the prepared cake pan and cover it with aluminum foil.
Step 2: Place a trivet inside an 8-quart Instant Pot and pour in the water. Carefully position the cake pan on top of the trivet and secure the lid. Set the Instant Pot to pressure cook on high for 40 minutes.
Step 3: After cooking, follow the manufacturer’s instructions for quick release before unlocking the lid. Remove the cake pan from the Instant Pot and discard the foil. Allow the brownies to cool for 15 minutes before inverting them onto a cutting board. Serve warm or at room temperature for optimal enjoyment.