I took this drawing from a product design website after I finished my cookie jar painting (below). Before I painted I had made several drawings and had a bit of a challenge to figure out the extension on the lid, it dipped a bit and stuck out, but the plastic didn't hold light or shadow to create the form correctly. I certainly could not attempt a painting until I solved a drawing, but I eventually did.
The top in the illustration might have helped me see the differences in the shapes.
Whatever. The cookies tasted particularly good, but after we had eaten some of them I saw a painting. Another kitchen item was moved upstairs to the studio for a few days. The first time someone asked "What happened to Elizabeth's cookies?" (my niece had baked and brought them in the jar for Christmas) I was tempted to say "What cookies?"
This crazy shaped, tilted top cookie jar is preserved forever in paint and the contents were delicious. Perhaps this will be next year's Christmas card.
She Brought Cookies, 10x7 on oil paper c.2018