This, more or less, is what Magic Mille (milleaccendini) is doing in this video:

We're gonna use a condom, but this time it's gonna be mango-flavored. Let's start. First thing: let's take some Nutella and put it on the top of the bottle, creating some kind of Nutella cap that will be fundamental for the Nutella-Coke-Mentos reaction. Good, now we open our condom and we put Mentos in it. Not just one, two or three, but five Mentos, since we found out during previous experiments that 5 is the best quantity of Mentos in terms of maximum reaction. Now we're going to seal everything with some tape. Perfect: Nutella, Mentos… now we're gonna let the Mentos drop on top of the Nutella, and that's enough for… and here's the reaction!

Stick around for the climax, folks.