I actually love to collect lavender Pyrex, I moved to a new residence and stored my Pyres under the stove. Then I got nothing but headache, the dishes started getting a backed on mess from the constant heat generated by my cooking. Now I had to find a solution.
Thank God for the easy of goggling the answer. I had to get online looking for the answer to clean it. Well ! with no help I finally stumbled on the recipe to clean pots and pans and it works great. When heat made the problem , you need heat to fix the problem.
Directions to Clean:
Fill your Pyrex dishes with about 1/2 cup baking soda and covered the bottom with white vinegar. Put Into the oven at 250 for cook for about a 1/2 hour.
Then the stain will come off in sheets! No scrubbing-no no fuss. This was a blessing to clean. I salvaged my dishes and you can use this same method on other pots and pans.