It’s soup season!  Or at least it should be.  Some would say that 60-degree days in December are a blessing, but I must confess that I find them downright disturbing — an unmistakable sign that all is not well with Planet Earth. 

Thankfully, in spite of the wacky weather, the earth still manages to produce many beautiful and delicious vegetables to delight our senses.  Last week’s CSA bounty included potatoes and baby leeks.  When those two things simultaneously appear in my kitchen, potato-leek soup is the inevitable result.  I don’t see any other choice, really.  (Does anyone else have this problem?)

As a result of my strongly-held views about the beauty of the potato-leek combination, I’ve made plenty of potato-leek soup in my life.  This time, however, I wanted to include some other ingredients from the CSA box as well — namely carrots and celery.   While my homemade vegetable stock simmered, I consulted my go-to cookbooks to see whether this combination made culinary sense, and, if so, how to execute it.  

I found two recipes that were close to what I envisioned.  Mark Bittman’s How to Cook Everything has a potato-carrot soup with a leek variation, and Marcella Hazan’s Essentials of Classic Italian Cooking has “minestrina tricolore,” which is potato soup with onions, carrots, and celery.  Neither of these matched my available ingredients exactly, but collectively they inspired the confidence to go ahead and do my own thing based on what the weekly CSA had provided.  

Recipes for the soup and for my quick vegetable stock follow.  The soup was great straight out of the pot and even better the next day.  If you try it, or an adaptation of it based on your taste preferences and what you have handy, then please report back. 

Golden Potato-Leek Soup (with vegan option) 

Ingredients

The vegetable quantities below are purely a function of what I had available — feel free to vary any or all of them based on what you have and what you like.

• 2 tablespoons butter (or olive oil)
• 2 lbs potatoes, scrubbed, peeled (optional), and cut into large dice 
• 3/4 lb carrots, scrubbed and cut into small dice
• 3 oz celery, washed and cut into small dice
• 4 oz baby leeks or leeks (I would’ve used more, but that’s all I had), white and light green parts only, thoroughly washed and sliced in 1/4 inch rounds
• 6 cups homemade basic vegetable stock (see recipe below) or water.  Making the stock is almost as easy as drawing water, and using it adds a ton of flavor.  I’m therefore going to encourage you strongly to use stock, but please, please not the kind that comes in a can or box!  I have yet to find a brand of store-bought vegetable stock that I can trust, and some of the ones I’ve tried are downright off-putting.  If you don’t have homemade stock, then just use water.  
• Salt
• Warmed whole milk (or additional stock or water), as needed to adjust the soup’s consistency 
• Parmigiano-Reggiano, to taste (optional)

Instructions

1. Melt the butter or oil in a medium soup pot over medium heat, then add the leeks, carrots, and celery.  Cook, stirring frequently, until the carrots and celery have softened.
2. Add the potatoes and a pinch or two of salt, and cook a couple minutes longer, being sure to coat the potatoes well with the vegetable mixture.
3. Add the stock and bring to a boil, then lower the heat and simmer gently but steadily until the potatoes are very tender (about 20 to 30 minutes).
4. Puree the soup with an immersion blender if you have one (and if you don’t have one, then put that on your holiday wish list!), or using a food mill or blender.  I like potato soups pureed until smooth and creamy, which in this case also results in a lovely golden color, but you can puree only partially or not at all, as you wish.
5. Stir in the warm milk (or stock) until the soup reaches your desired consistency.  If you don’t puree, then it’s possible you will not need to add milk for the purpose of thinning the soup, but that should not stop you from adding milk if you like it. 
6. Stir in freshly-grated Parmigiano-Reggiano, to taste.  Mmmmm, P-R is the embodiment of the “umami” flavor in all its glory!!!  (Yes, you guessed correctly, I used a lot.)

Basic Vegetable Stock

The key ingredients here, of course, are the beautiful and colorful trio of carrots, celery, and onions.  You can pretty much use whatever proportions make you happy.  Even if you’re missing one of the “big three” altogether, don’t worry, you will still end up with something much more flavorful than plain water.  

You can add a number of other things, too, like garlic, tomatoes, potatoes, leeks, mushrooms,turnips, peppercorns, allspice berries, and/or herbs.  The purpose for which you’ll be using the stock should serve as a guide for which of these flavor enhancers to include on a particular day, but there are some, like peppercorns and certain herbs, that I use virtually every time.  You also could roast the vegetables before adding them to the stock pot, to lend a richer, more complex flavor, if you had the time and inclination.  

The variations for vegetable stock really are endless.  I’m constantly experimenting and encourage you to do so as well.  What I’ve set forth below, however, is what I generally do when I need an uncomplicated, neutral stock in a bit of a hurry.

Ingredients  

• 1 large or two small onions, peeled (optional) and cut into eighths
• 2 or 3 medium carrots, scrubbed, peeled (optional), and cut into large chunks
• 3 or 4 stalks of celery, washed and cut into large chunks (it’s OK to use the leafy tops and the white bottoms)
• 15 (more or less) sprigs of Italian flat leaf parsley, cut in thirds, or a somewhat larger quantity of parsley stems (if you’re in the habit of saving them)
• One or two bay leaves
•  A few sprigs of fresh thyme, or 1/2 teaspoon dried thyme
• 10 to 15 peppercorns

Instructions

1. Put all the ingredients in a medium stock pot, add 8 cups water (or enough to cover the vegetables by at least an inch, and bring to a boil.
2. Adjust the heat so that things kick along at a gentle simmer until the vegetables are all very tender, about half an hour.  You could let it simmer longer than this if you have time, but my experience says that anything beyond an hour isn’t worth it. 
3. Strain and use immediately, or cool and refrigerate or freeze for future use.  Make sure the stock cools completely before covering.  If refrigerating for more than a couple days, bring the stock back to the boil every second or third day to extend its useful life.