Friday, April 10, 2009

Box Mix+Soda=Cake

Regular food coloring does not make for good cake colors. It does ok in icing, but not in baked goods. So when I saw the picture of a bright rainbow cake on the web, I had to track it down. I've heard of the gel colors, but haven't really had reason to look into it, but this intrigued me. Then I found out it was made with a box of mix and a can of soda and I became obsessed.

My apron explains a bit of why I'm so excited about a psychedelic, neon colored cake.

Rainbow Cake Inspiration - Rainbow Tie Die Apron
    Rainbow Cake Ingredients
  • 2 boxes white cake mix
  • just under 24 oz. clear/light soda (reg or diet) like Squirt, ginger ale, plain soda water.
Here's what it takes to make a rainbow cake - if you're also conducting an experiment. To just make it and be done with it, it takes half this cake, topping, pudding, and pop. Duncan Hines was 4/$5 and Betty Crocker was 2/$4 at Ralphs today so I got two of each just to see if they came out different. Betty Crocker makes the tubes of gel coloring, look in the frosting section, I had to have a store manager help me find it.

Rainbow Cake Ingredients
Click the picture if you want the gory details. It'll jump to a separate entry and load a whole load of pictures. This is the summary version, here.

The batter looked great and the cake looked just fine too.

Rainbow Cake innards

After finishing, though, I'd seriously consider adding
  • 2 eggs
while the texture was light and moist, the cake was really sticky with a gummy finish, yet fragile. Yeah, that cake was cut with plastic knives, but it still crumbled like a sandcastle. I think replacing up to a third of the soda with an egg (per box) might improve it. But make no mistake, a box of cake and a can of carbonated soda - even just soda water - will net you edible cake batter that becomes an actual cake.
  • Preheat oven to 325F.
The Colors, the Colors!

Divide cake batter into roughly (or exactly) 6 equal parts in other bowls. Color mix/soda batter to desired red, orange, yellow, green, blue, and purple hue with gel colors. Betty Crocker makes some, look in the frosting section. Add 9-15 lines of 1.5" of gel color from the tubes or just eyeball it until it looks good. Do all colors before starting to fill the pans.

6 colors of Rainbow Cake Batter

To get a rainbow, dump about 2/3 of the red in center one pan, slightly less than 2/3 of the orange in center of red, then half of the yellow in the orange. Similarly, Dump 2/3 of the purple in the other pan followed by slightly less than 2/3 of the blue and half of the green.

Rainbow Cake first half

Then switch sides and continue to layer with remaining colors in order.

Rainbow Cake pans filled

This method of regular and reverse rainbow order helps balance out the inevitable asymmetry of color usage. You can use a different method, scattering blobs or trying for even layers, but this method works to put every color in every wedge slice.

Rainbow Cake Slice

I decreased the oven temp to 325F and tented the cakes with Al foil at about the minimum time on the box for the pan size to reduce browning. And like this when they came out! These cooked about 45-50 minutes (18+15+15 on timer plus time to shift, tent, etc). I let them sit in the pan for 15+ minutes to solidify and make them less fragile.

Rainbow Cakes, done!

Soda Verdict: Before starting, I knew that diet soda was an option, but I don't eat aspartame. Apparently any light colored soda would work, but I wanted to know if it was just the carbonation or if it needed some of the other soda ingredients. From my tests, all carbonated liquids worked fine. I did not try any non-carbonated beverages. Squirt and Club Soda tasted the best, probably due to adding salt and the fact that Shasta ginger ale is nasty. It worked fine to make cake but did not add anything. After cooking, I think it all tasted the same. And I would add in an egg per box if available to see if it helped with making the cake less fragile.

Gel Color Verdict: The colors, they were glorious and entertaining. Gel colors are awesome.

Bake Mix Verdict: There was about 45g more mix in the Betty Crocker, which slightly overshot the "517g" listed on the package. Both cakes taste a little chemically to me, but not much and about equal. The textures appeared the same as did the color mixing and baking. For all intents and purposes I can't tell them apart for this application.

The Frosting

But wait! There's more! 2 more ingredients.

  • 8oz. tub of non-dairy whipped topping (Cool Whip) at fridge temps or so.
  • 3.4 oz package of dry Vanilla instant pudding
  • 2-3 oz soda or seltzer (or milk, if it won't be sitting out long)

    Mix ingredients in any order with your favorite mixing technique. Frosting should be smooth and form stiff peaks. Spread on cooled cake. (Repack in container and refrigerate if not needed immediately.) Carefully stack another layer on and keep frosting. If it's goopy add another T of liquid and keep going. Cut into your fabulous Rainbow cake and show everyone the pretty colors!

Pudding Verdict: Vanilla over Lemon, no contest. Lemon is tolerable; Vanilla is lush.

This cake, it is not organic. It's likely not even recognized as food by the intestines. It is pretty fun to make and eat. I had the notion that doing this could avail vegans of cake sans eggs, but the sorts of people who are vegans tend not to overlap much with the sorts who buy boxed cake mix and soda. (Much like those who eat hummus tend not to overlap with those who eat ham, and thus the world is deprived of quick availability to my favorite, the ham and hummus sandwich.) If you let your kids eat food coloring (some people have really bad reactions), it's an extra good project because there are 6 spoons and spatulas that need to be licked clean. And then it turns into cake.

Rainbow cupcake innards



Anonymous said...

This cake is just groovy man!

I've never seen this one before, but I'm sure going to try it soon. I know this kids will really like it.

Kathy S.

CrankyOtter said...

To be clear, you can also use the food coloring on cake made the normal way with eggs and oil or eggs and applesauce. But it's so much more work and the point is really the color in this one, that I doubt it's worth making a healthier/heftier cake to support a bunch of chemical colors. Besides, it's really fun to make cake with soda pop.

gail said...

This is sooooooo FAR OUT, Erika! I'm channeling the words to Age of Aquarius --- 'harmony and understanding' ---- "peace!"


Brings back memories of my mis-spent teen years during the late sixties/early seventies.

I'm on my way to Wal-Mart to shop for Easter dinner and was thinking of a dessert that wasn't tooo sugary --- I'm gonna try this --- with Club Soda (severely allergic to aspertame in all it's guises) and will add an egg per box ...

May not do all the colors --- but try something retro-pastel Easter style

Thanks for the step-by-step procedure --- printing out now!

BTW: Cathy Mann now has a blog --- have you seen it?

CrankyOtter said...

Oooh, haven't seen the Cathy Mann blog. I liked her most recent "Defender" (on shelves now!) so I'll have to check it out.

To make with 6 colors took a while, like 80 minutes, so fewer colors is called for.

I had the feeling I should have been listening to some Phish or GD, but had to make do. So much fun though. Just before I moved, I had been inspired by Martha Stewart to make one festive cake a month for a year. I moved at cake 5, and it feels like I'm picking back up where I left off.

gail said...


I made the cake --- with only blue and red -- which I could only get to the pastel stage with so much batter in each bowl --- however --- I did reduce the liquid (used Club Soda) and added two eggs.

The cake turned out nicely --- but it is still crumbly --- even with the egg addition.

Also --- another oops --- used French Vanilla pudding instead of Vanilla and ended up with a pastel yellow frosting --- in keeping with the pastel theme I had going .. 8 - )

But it was very tasty and with the low sugar content easy to enjoy!

Thanks for sharing ....

CrankyOtter said...

Oooh! I was hoping your cake turned out. So ok, maybe the eggs are just me being crazy. Back to the 4 ingredient cake.

I still have one of the two sets of cakes. I ate some, it tasted like cake, but now I'm tired of it. It hasn't had any issues with, uh, weathering yet - it is unfrosted although I have the frosting sitting back in the CW tub in the fridge, I'm using it on strawberries instead.

Sherry said...

I love hummus and I'll eat ham. I'm really more of a bacon person...

CrankyOtter said...

Bacon is excellent, but harder to eat in a cold sandwich, as I don't usually keep it ready to go. I do buy pre-cooked stuff that's ready in 22 seconds microwaved, but that still needs the cooking. My brother got 12 pounds of bacon for his birthday this year, from me, so I'm not exactly anti-bacon...

indy said...

Wow. Seriously. I just found your "Box Mix + Soda = Cake" post while searching for club soda cake mix cupcakes. (I've read that the size of a standard cake is harder to pull off.)

I never thought to jazz it up with gel food coloring. It's so mesmerizing.

CrankyOtter said...

Thanks! It is totally possible to dump a can of soda into a box mix and get cake. The texture is not as good as adding the usual ingredients but it can be done. I've gone back to using eggs and oil (or applesauce to replace oil). Then I bought enough gel colors to last the rest of my life.

CrankyOtter said...

One more suggestion for the rainbow cake - decorate the top of the frosting with Skittles. A (genius) friend of mine did this for the youth group she sponsors and they loved it. It also means you can use a single color frosting and still have colored decorations.