Barkeeper's Friend or Baking Soda mixed with hydrogen peroxide into a paste. Then a lot of scrubbing with a non abrasive medium. I really like Scrub Daddy sponges.
Here's a step by step site that should help if Barkeepers Friend doesn't work
I have used an SOS pad carefully though, so it doesn't leave scratch marks
Fill a sinkwith enough water to cover them. Add two to three fabric softener sheets. Aoak overnight and thr next morning they ahould wash clean without scrubbing.
A Mr. Clean Magic Eraser will quickly do the trick for you!
Baking soda and hot water
I use something call boni
Use Bar keepers friend and a little water.. Best wishes
I use a product called Cerama Bryte...it is similar to Bar Keeper's Friend (which I have never tried)...here is an example of what it can do...https://www.exquisitelyunremarkable.com/2018/04/tea-cup-planter.html
here are some ideas for your cleaning
Use Brillo and comet
Use bristle brush with comet
Make a paste of baking soda and water, apply it to the burn mark, let set overnight, scrub in the am with the rough side of a sponge from the dollar tree. Repeat if needed.
I use TSP powder mixed with water and a scrubby pad or Bar Keeper's Friend.
This works well: https://www.youtube.com/watch?v=BCDLmVGu4WI
Hi Diane, In a large pot, combine 3 cups vinegar, 4 cups water and 2 Tbsp citric acid, and bring to a boil. Set one CorningWare dish into the boiling mixture for five minutes (the water must cover the dish). If necessary, scrub wet CorningWare with an S.O.S pad. Once dry, your dishes will look brand new.