Never tried anything like this, but you asked for ideas...
Can you even frost the cake with them w/o them reacting?
If they only react w/ water, you may be able to get them in a fat-based frosting.
Especially if you use this for the middle frosting of a two-layer cake, this may work.
If you really want them in the cake itself, and they don't react with the baked cake (it has water still, I bet they do)
you could make a double-layer cake, and insert them into the hidden surfaces (e.g., the bottom of the top layer and the top of the bottom layer).
Just make some slits and put them in.
cooking.stackexchange.com/users/160/derobert
I was speaking to a chef at the weekend who makes chocolate with space dust in it, and this works ok because the chocolate doesn't have any water.
You might be able to make chocolate chips which have space dust in them, mix these in to you mixture and hope that the cake sets before the chocolate melts and lets the space dust get into contact with the moisture in the mix.
Not sure if there is anything you can do to the chocolate which will raise the melting temperature, which would also help.
EDIT
: I asked this question which might help.
cooking.stackexchange.com/users/210/Sam Holder
As stated, moisture is your enemy in this endeavor.
Do some tests to see what does and does not react with the pop rocks.
Then if you find something that will be able insulate the pop rocks from the moisture involved in making a cake, experiment in coating the pop rocks to protect them.
After this, you can go about your cake making being careful of the pop rocks.
My guess is that something fat based might coat the pop rocks without making them fizz.
This might not end up in a very desirable end result though.
cooking.stackexchange.com/users/63/plor
I've had success before making a rich chocolate torte, then putting the pop rocks in the base mixture.
There is a light crackle lost initially but it's good enough to refrigerate and still have a decent pop that day and the next.
I certainly surprised my guests with it!
Here's the original Heston Blumenthal recipe I used .
cooking.stackexchange.com/users/2389/Gary
Pop rocks is a candy made with carbonation, so that while it dissolves on your tongue, the embedded bubbles pop.
Any exposure to water will make the pop rocks into just an expensive brand of sugar.
Same goes for thorough mixing, which would break down the candy and release the bubbles.
I would try folding the pop rocks into butter cream frosting, or sprinkling on top.
Hopefully the relatively low water content of the frosting will keep the pop rocks from dissolving before the cake is served.
Time is your enemy here, since it can absorb water from the atmosphere.
cooking.stackexchange.com/users/114/Crispy
I want to build a cake with Pop Rocks / space dust. Has anyone got any ideas on how I would do this? If I add the Pop Rocks straight to my cake mixture, then I believe it'll just react. Any suggestions?
Cooking cakes with Pop Rocks / Space Dust
cooking.stackexchange.com
<cake><pop-rocks>
cooking.stackexchange.com/questions/715
cooking.stackexchange.com/users/209/seanyboy
Moisture and time are the enemy here, but a rich chocolate or fat-based frosting might prevent the pop rocks from absorbing water and reacting. Moisture and time will make this difficult to achieve. You can try mixing into something fatty, like butter cream frosting.
Moisture will be a problem here. You will need to work fast. Try mixing into the base of a torte or into butter cream frosting. The fat might protect them from moisture.