Grocery Store "Amnesia"

 I won't use the other a-word, too predictable. 

  I don't keep a grocery list. Now I just replace the regular items as needed. But about 3 weeks ago, I noticed one item was almost depleted, so I added it to my mental shopping list. But when I got back from grocery shopping, I realized I had forgotten to buy it, so I wrote it on a slip of paper near my phone.  A few days later, I noticed another item was also running low, not a regular purchase, so I wrote  that on the piece of paper with the first item, noting that both items started with the letter c. When I arrived home after the next shopping trip, I realized I had bought the second item, but again had forgotten the first. 

  I was at the store yesterday and knew I had to get that forgotten item, the one beginning with the letter c which was on the slip of paper on the counter, and it was not the Clorox. I could not remember what that item was. It started with c, was not routinely used, and I could recall that it was packaged in a box, in multiple servings but I could not remember what It was. I walked down each aisle in the store, thinking I could spot it, but that was fruitless. The first thing I did when I got home was to look at that piece of paper with the several-times-unpurchased item. A rectangular package, seasonable usage, multiple sections:  Of course, it was c****. How could I have not been able to recall that!