Here's Why Using the Correct Measuring Cups Is the Very Best Way to Ensure Baking Success
Measure for measure, there's nothing more key.
As a semi-regular home baker and longtime cookbook editor, I get loads of questions from friends about baking. "What's the best layer cake for birthdays?" they ask, or "Can you send me your favorite brownie recipe?" I never tire of questions like these, and happily oblige by forwarding an online recipe or pulling a cookbook off the shelf and texting a photo of an especially splattered page. I am surprised, however, when those same friends report back that the recipe turned out just alright. How could that be, I wonder, when I've made the same recipe dozens of times. The poor recipe usually gets blamed, but what I've come to conclude, over years of watching cooks in their home kitchens, is that it's mostly the result of faulty measuring. (Other factors include wonky oven temperatures and strange substitutions, but inaccurate measuring is the biggest culprit.)
My husband, who loves a non-kitchen home project of his own, lives by the adage, "Measure twice, cut once." That's important for carpentry, of course, but for baking, I prefer to measure it right from the outset. I don't have time to measure anything twice. And the key to measuring properly is simple: Use the right cups and spoons! First, know the difference between dry and liquid measuring cups, and don't make the mistake of using them interchangeably. I've watched friends measure flour in glass liquid measures, and it never ends as well as it should. That breaks my heart a little every time. (All that wasted effort!)
Liquid Measuring Cups Versus Dry Measuring Cups
To avoid such mishaps, first choose a set of graduated metal cups with firmly attached handles for dry ingredients (flours and such)—we like Cuisinart's classic set ($9.88, amazon.com). I avoid plastic cups, since they can't (or shouldn't, rather) go into the dishwasher, and they're prone to warping over time. I've had the same set of trusty metal cups for close to 20 years. For liquids, including milk and oil, use glass cups, with handles, spouts, and clearly marked measuring lines, ideally get cup, pint, and quart glass measuring cups, like this set from Anchor Hocking ($15.96, amazon.com). Again, I prefer not to use plastic, though if that's what you have, it's fine as long as you measure correctly.
The Correct Way to Measure
Just as important as choosing the right tools knowing how to use them. For flour and other dry ingredients, begin by aerating quickly with a flick of a whisk or fork. (Flour tends to compact as it sits, and you don't want to measure anything that has been sitting in a bag or jar for too long.) Use a spoon or small scoop to fill the cup up and over the top, and then a straightedge to level it. (This is often referred to as "spooning and leveling.") Do not bang the cup on the counter, or shake it back and forth to try to level it. Both methods will give you more flour (and thus, heavier baked goods) than you're after. This is true for most dry ingredients, though brown sugar is usually firmly packed. You'll know that you've measured properly when you overturn the cup and out falls a solid block of brown sugar.
Set clear liquid measuring cups flat on the counter before pouring in ingredients, then crouch down to eye level to get an accurate measure (again, clearly marked lines are key here). The spout is important for pouring liquids into your mixing bowl. And because I'm fairly rigid about such things, I use a silicone spatula to get every last drop out of the cup, especially when measuring sticky things like honey or molasses. (Pro tip: If a recipe includes oil, I always measure that first, and the other liquids later, so they have less of a tendency to stick.)
It Really Does Make a Difference
And though I've written about proper measuring for years, I'd never actually bothered to test the differences, until now. For the sake of backing up my claim, I measured a few different ways, then weighed the ingredients to gauge the difference. Turns out that measuring a cup of flour accurately, as described above, resulted in 122 grams. Dunking the cup measure directly into the flour (rather than spooning and leveling) gave me 137 grams. And using a glass measure, shaken back and forth to level (as I have witnessed!), resulted in 154 grams of flour, a whopping 32 extra grams. Who knew? (Well, I did, in theory, and now you do, too!) Happy baking!