In my kitchen, I have a small collection of cookbooks, which I consider prized possessions. One of them, the classic Betty Crocker Cookbook, was a wedding gift, and trust me, it’s seen more than its share of splatters and dog-eared/ripped pages. And I wouldn’t part with it for anything.

Another features 100 things to do with an ordinary cake mix. It is fabulous — or, I should say, it used to be.

Here’s the problem: About 10 years ago, cake mix manufacturers got the bright idea to shrink the contents of a standard cake mix rather than increase the price. Sneaky, right? And what a terrible decision that was. What used to be the standard 18.25-ounce cake mix suddenly shrunk to 15.25 ounces. Have you noticed this?

That might not be a problem if you’re using that cake mix to make the cake according to the back-of-the-box instructions — which is going to turn out noticeably smaller, by the way. But if you’re into hacking a cake mix (where the mix becomes a single ingredient in a much better recipe for anything from waffles to cookies to much-improved cake), it’s a problem. Those recipes in my little “100 Things” cookbook all assume an 18.25-ounce cake mix. And why not? That’s the way it had been for decades.

Does it really matter? It does, because unlike cooking a pot roast or lasagna, where exact measurements are not critical, baking relies on chemical reactions. Exact measurements do matter.

But there’s good news! If your cake mix is too small, it’s easy to remedy. Here are three options:

Method No. 1: Purchase two 15.25-ounce cake mixes. Add 3 ounces (6 tablespoons) from the second mix to make up the difference. Keep the balance of that second mix in a tightly sealed container to use the next time you make this cake.

Method No. 2: Purchase a plain yellow cake mix and empty its contents into a glass mason jar. Keep it tightly covered and stored in the pantry. When you need to supplement any flavor cake mix so that it is a full 18.25 ounces, remove 3 ounces of the yellow cake mix and add to the 15.25-ounce cake mix. Yellow cake mix has a neutral flavor, so this is not going to adversely affect the outcome.

Method No. 3: Make your own “cake mix upsizer”

To upsize white and yellow cake mixes:

1 1/2 cups all-purpose flour

1 cup sugar

2 teaspoons baking powder

1/4 teaspoon baking soda

To upsize chocolate mixes:

1 cup and 2 tablespoons all-purpose flour

1 cup sugar

6 tablespoons cocoa powder

2 teaspoons baking powder

1/4 teaspoon baking soda

Whisk all dry ingredients together and store in a clean mason jar. When you wish to increase a 15.25-ounce cake mix to 18.25 ounces, add 3 ounces of this mix to your existing cake mix. Store that remainder in a tightly closed container, like a glass canning jar with a lid, on the pantry shelf. Yield: About 6 portions.

There you go — a fairly simple remedy for a very annoying problem. Happy baking!