In a mason jar whisk together melted butter, egg yolk, sugars, and vanilla.
Add flour and salt mix well.
add chocolate chips. Mix
Top your mason jar with tin foil.
Place 1 cup of water in your pressure cooker along with the trivet that came with it.
Place the foil-covered mason jar on the trivet.
Close your pressure cooker and cook on high pressure for 7 minutes. Or 5 if you want your cookie to be extra gooey.
Remove lid immediately after the cooking process has ended.