To turn it into a bowl, do the following:
Heat the oven to 215°F.
Cover a cookie tray with aluminum foil. Turn a Pyrex bowl upside down on the cookie tray. Cover that with foil pressed tightly into shape.
Put the foil covered bowl into the oven to preheat. After a few minutes, place the doily on top of the bowl and close the oven door.
Within a minute (or less) the PLA doily will begin to slump. Watch it closely, you want it to start to curl but not completely lose shape.
Open the oven door, place your hands on top of the doily and press down to shape it to the bottom of the bowl. (It's not really hot yet, just soft.)
Take it out and it will harden into shape in a few seconds.
Use a large bowl for a wide lace bowl, or a small one to get a ruffled effect.