The things that do NOT scale well are leavened goods ... you can't just mathematically increase or decrease cakes and cookies (doubling and halving is usually safe).

For main dishes ... the added depth of the commercial-sized pans usually means it takes longer to simmer down a sauce or to reduce the risotto liquids. And it gets hard to stir and blend in ingredients, again just from the added volume.

Can she make 3 pans of it, each for 10-12 servings? That would be manageable ... do all the prep once, and divide the oil, rice, etc ... and have one honking kettle of broth for them all.

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Holding them for service? Make sure you have GOOD temperature holding practices.

Sound advice from Lazygardens.

Risotto for 30 isn't that hard, especially if it's a side rather than a main. The thing is, it's almost impossible to make in a kettle. I mean, it'll be rice, but getting the starch to shed and the right amount of evaporation in a tall, deep vessel, is awfully hard. If she has room to do it in a full sized pan over a couple of burners, it shouldn't be too hard, especially if she has a paddle to stir with. It's much easier than a spoon for that kind of quantity.

If there isn't a holding oven or steam table or something, and it can't be kept on the stove, it would be better to cool it completely, when it's just barely done, and refrigerate it. The shallow pan makes cooling easier too. It can be heated up in smaller batches, in a regular skillet, with some additional stock if there isn't enough burner space for the whole pan. If there's an oven it can be reheated in, that would work too, with a little adjustment of the liquid, and a few stirs. Not optimal, but okay for hungry kids. :)

If that's not an option, and it won't be held for very long, it can be covered with foil and wrapped in Turkish towels (hot, steamy ones), but that's risky, especially for feeding children who are more susceptible, and heating it completely to pathogen killing temperature would be problematic. It should remain out of the danger zone with the Turkish towels, but the temperature must be checked at various points through the whole pan, and if there's a chance it'll need to be rewarmed, it's better to start with a system where it needs to be rewarmed than doing it on the fly. Theoretically, there isn't much in risotto that would develop bacteria that radically, but it's not worth the risk.

For scaling recipes, the important thing to remember is that salt doesn't scale at the same rate as the bulk--you generally need less--and other seasonings also have a different rate. It's also much easier to scale by weight, including liquids, than by volume.

Any recipe that calls for adding liquid to cover, or any such thing where there's an interaction between the size of the bulk, the size of the pot, and the amount of liquid, is going to be wrong. Again, using a shallow pan is going to be the most like home cooking, but the amount of liquid, and its consistency are going to be off for making jus or gravy. It could need to be reduced, or added to and reduced. A good strategy is to make a separate liquid for serving, and save tonight's pan juices for tomorrow's meal.

Most recipes can be scaled to twice their size without adjustment other than being careful of too much salt. Three times, is trickier and requires some general feeling of knowing how to cook to do on the fly. Two times done thrice (three separate pans) might be enough to feed her 30, though. A good alternative is to start with recipes already designed for volume. If you search the 'net, you can find all kinds of catering recipes as well as restaurant recipes. You might even find analogues of the recipes you do at home, where you can crib quantities by matching ingredients. Be careful, again, of the salt, though. Most catering/restaurant recipes have too much salt, because it's harder to taste complex flavors in un-calm environments. Young people have more acute taste buds and generally hate food that's that salty. A pretzel covered with coarse salt, yum, a piece of chicken with a fraction of that amount of salt? Stank face.

Thanks! I will pass this on to her. In this case, I think the risotto might get done 1/2 hour before the campers eat. I did warn her that a tall, deep pot wouldn't work.

We recently watched a British restaurant competition TV series, where one of the contestants tried to make a large quantity of risotto. It took waaaaay longer to cook than expected (never did really get cooked properly before he _had_ to serve it), was burned on the bottom at one point (with predictable flavour results) and was stodgy and gluey. One of the judges, Raymond Blanc, commented that it should have been done in multiple smaller batches.

She texted me pictures of the kitchen at the new camp. 8 burner commercial range, similar size griddle, one of those continuous dishwashers, walk-in coolers, etc. When she returns from camp, Daughter-san is always mocking my measly little four burner residential range . . . she gets spoiled, cooking on commercial equipment.