Cooking for Many

I have four days to perfect and then multiply a cold carrot soup recipe. I've done a bunch of hunting and research and finally decided on the following recipe for Cold Carrot Soup with Orange and Cumin.

INGREDIENTS
1 teaspoon canola oil
1/3 small onion, cut into 1/4-inch slices
2 teaspoons ground cumin
5 medium carrots, diced
6 cups vegetable broth
1 teaspoon sea salt, optional
1 cup fresh orange juice
2 teaspoons fresh lime juice, optional
1 teaspoon grated orange zest for garnish
6 sprigs of fresh dill for garnish, optional

1. Heat the canola oil in a medium-sized pot set over medium-high heat. Add the onion; sauté, stirring for 2 to 3 minutes or until soft and translucent.

2. Stir in the cumin; cook for about 2 minutes to bring out the pungent aroma of the spice. Stir in the carrots, stock or broth and salt, if using; simmer partially covered, for 30 to 40 minutes or until the carrots are tender. Remove from the heat and let cool.

3. Transfer the soup to a blender or food processor, fitted with a metal blade, and process until smooth. Blend in the orange juice and lime juice, if using. Transfer to a bowl or storage container, cover and refrigerate until well chilled.

4. Serve cold in chilled soup bowls. Garnish with orange zest and dill, if desired.

Makes 4 servings.

In my research I noticed an awful lot of similarities between the recipes and I've started thinking I could do one from scratch with no recipe whatsoever.

This recipe is very simple compared to many others that called for more exotic ingredients. I've worked with fennel bulb only once before and don't want to try it here. I wanted to avoid the seemingly unavoidable chicken stock as I will be feeding some vegetarians (which also ruled out any recipes involving sour cream or its like).

The problem I am having at this point is trying to size this recipe up to the Herculean portion that is required. It says it makes "four servings" but it doesn't exactly say what a serving size is. If I go with the industry standard, it's an 8 oz. cup, but I can't see how 6 cups of veggie stock, 1 cup of O.J. and all the moisture from the carrots could reduce down to 32 ounces of liquid. Certainly you will lose some moisture as the stock boils, but I really can't see it reducing down that much.

Eventually I'll have to size this thing up to make 3 gallons of soup!! That's what I was asked for, and that's what I want to deliver.

I have come to the conclusion that the only way I can work this out is to make one batch of the soup from the recipe and then measure it. After that is will be a simple matter of multiplying everything up. And no, I don't plan on making all three gallons at once, but will make three one gallon batches. It'll just keep things simpler that way. But I still need to know how many ingredients to buy.

And as mentioned before, I only have four days...

ADDENDUM:

I made the recipe at a party and it came out almost perfect and produced a little over a quart of soup. I am going to add some sweet potatoes because the soup wasn't as thick as I would have liked. I've got a kitchen lined up (mine is a little small) and now all I have to do is buy the ingredients and get cookin'!