Easy Box Cake for a Crowd — Feeds 12 for Under $5
Easy box cake is one of those things I will never apologize for. If you’ve ever needed a dessert that feeds a crowd, costs almost nothing, and comes together in about 35 minutes flat — this is it. One box of cake mix, three eggs, a cup of water, and half a cup of oil. That’s all you need. I made this one ahead of Sunday lunch for our family, and let me tell you — nobody complained. Nobody ever complains about cake. I frosted it right in the pan with store-bought vanilla frosting because I am not fancy, y’all. I am just someone who loves feeding people good food, and sometimes good food comes from a box. There is zero shame in that at this table.
This post contains affiliate links. As an Amazon Associate I earn from qualifying purchases. If you purchase through my links, I may earn a small commission at no extra cost to you. Thank you for supporting StephanieCooksForACrowd.com!
How I Make Easy Box Cake for a Crowd
This easy box cake has saved me more times than I can count. Sunday lunch, a last-minute potluck, a neighbor who just needs something sweet — a box of cake mix is one of the best things you can keep in your pantry. I always have two or three on hand because life happens and dessert still needs to show up.
Here is what I used for this one:
🎂 One box of cake mix (I used a standard 15.25 oz box)
🥚 Three eggs
💧 One cup of water
🥑 Half a cup of avocado oil
🍦 One can of store-bought vanilla frosting
Mix everything together with a hand mixer according to the box directions, pour it into a deep 9×13 pan, and bake for about 30 minutes. Let it cool completely before you frost it — I learned that lesson the hard way. Once it’s cooled, spread your frosting right on top and serve it straight from the pan. Done.
I used my Pyrex Deep 9x13 Glass Baking Dish for this one — it comes with a lid, which means I can frost the cake, snap the lid on, and take it anywhere. I also used my Pyrex Glass Measuring Cups for measuring the water and oil. These pieces live on my counter and I use them constantly.
When I filmed this, I wondered out loud whether you could use avocado oil instead of vegetable oil in a cake mix — I use it for savory cooking all the time because it has almost no flavor. Well, I went for it, and now it is the only oil I use in this cake. It bakes up beautifully with zero off taste, so that is what I reach for every single time.
The cake baked up beautifully, the vanilla frosting smelled amazing, and Sunday lunch the next day was everything. If you are looking for another easy crowd dessert, my 3 Ingredient Cherry Dump Cake is just as simple and just as loved at this table. And if you want even more inspiration, Food Network has a great article on how to make box cake better — check it out.
Feeds 12 people. Costs less than $5. Comes together in under an hour. Easy box cake for a crowd — this is the way.
The Tools That Live on My Counter
The three pieces I reach for every time I make this cake:
- 9x13 INCH: Includes (1) 9x13x2.75 inch glass baking dish with BPA-free plastic lid. This deep baking...
- GO DEEPER: At up to 50% deeper than the Pyrex basics dishes you know and love, there’s more room...
• A deep 9x13 with a snap-on lid. I frost the cake, snap the lid, and carry it straight to wherever the crowd is.
- ESSENTIAL KITCHEN TOOL: 2 piece set includes 1-cup, and 2-cup, measuring cups that are perfect for...
- EASY TO READ: Featuring bold and large measurements in both ounces and milliliters making this...
• The measuring cups I use for the water and oil. Nothing fancy — just the ones that live on my counter and never let me down.
- NO MORE LOST BEATERS: The snap-on storage case that comes with the Hamilton Beach hand mixer neatly...
- EASILY HANDLES A VARIETY OF RECIPES: With 6 different speed options plus a QuickBurst button for an...
• My trusty hand mixer. Six speeds, snaps into its own storage case, and whips a box mix smooth in about a minute.
Easy Box Cake FAQ
How do I make a box cake better?
A few little upgrades go a long way — I use avocado oil for a clean flavor, make sure not to overbake, and let it cool completely before frosting so nothing slides off. A good store-bought frosting and a generous hand make it taste like you fussed when you really didn’t. Honestly, a box cake done right beats a sad scratch cake any day.
Can I use avocado oil instead of vegetable oil in box cake?
Yes — and it’s all I use now. Avocado oil has almost no flavor, so it bakes up with zero off taste and the cake stays beautifully moist. I swap it one-for-one in place of the vegetable oil the box calls for.
How many people does a 9×13 box cake feed?
A deep 9×13 cuts into 12 to 15 squares depending on how generous you are. For my family of seven plus guests, one cake is usually just right with a few pieces left over. If I’m feeding a bigger crowd, I just bake two — it’s cheap and easy enough that doubling up is no big deal.
How far ahead can I make easy box cake for a crowd?
You can bake and frost it a full day ahead — just snap a lid on the pan and leave it at room temperature. That make-ahead, carry-anywhere quality is exactly why it’s my go-to for potlucks and Sunday lunch. One less thing to do on the day is always a win.
What frosting is best for box cake?
A good canned vanilla frosting spread right in the pan is my no-fuss favorite, and nobody has ever complained. Cream cheese or chocolate work beautifully too — pick what your crowd loves. Frosting in the pan means no layers to wrangle and no crumbs to fight.
Easy Box Cake Shopping List
Everything you need for this cake, all in one place:
More Crowd-Friendly Desserts You’ll Love
- Texas Sheet Cake — the big, chocolatey sheet cake that feeds a crowd and disappears just as fast as this one.
- Easiest, Most Delicious Coconut Cake — when I want something that looks a little fancier but is still completely doable.
- Pineapple Upside-Down Cake — a retro crowd-pleaser that always gets the “ooh” when you flip it out.
Want a little note from my table every Saturday? Join my weekly newsletter — recipes, family moments, and whatever’s happening at the Longstreth house. Sign up here.
Easy Box Cake — About Stephanie Longstreth
Stephanie Longstreth is the home cook, mom, and storyteller behind StephanieCooksForACrowd.com. She cooks for a family of seven in Florida — five kids, two cats, and one husband who appreciates a good meal. Four of her children came home through adoption, and family stories are woven into everything she makes and shares. Find her crowd-friendly recipes, weekly meal plans, and real family life on TikTok, Instagram, YouTube, and Pinterest @stephaniecooksforacrowd.