Sweet Potato Soup with Chilies and Corn

Sweet potatoes are a power food.  They are low in fat and sodium, naturally sweet-flavored, and have tons of nutrients (especially vitamins A and C and calcium).  But they’re not just good for you.  They also taste good — really good.

Sweet potatoes combine well with a wide variety of spices and flavorings.  And they can be prepared almost as many ways as “standard” potatoes (although the two are completely different plants and aren’t even in the same botanical family).

Yet most of us eat sweet potatoes only once a year (at Thanksgiving) and in one way (candied, usually with marshmallows).

That’s how it was for a long time in the Kitchen Riffs household.  We knew how delicious these tubers could be, but somehow we just never got around to preparing them on a regular basis.

Sweet potatoes invariably made for some of our tastiest Thanksgiving leftovers.  And every year we would ask ourselves why we didn’t have them more often.  Then the holidays would pass, and we would forget about sweet potatoes.

Until a few years ago, when we decided to break out of the box.

Transgressing Against Tradition

We struck a blow against conformity!  We forged our own path!  In short, we started eating sweet potatoes during months that didn’t begin with the letter “N.”

And our eyes were opened to a really versatile vegetable with marvelous flavor.

One of the tastiest dishes we discovered was sweet potato soup.

Recipe Essentials

Sweet potato soup is easy to make.   You just cut up sweet potatoes and cook them with vegetables (be sure to include aromatics) and other flavorings in some type of liquid, usually stock.  (Chilies and/or ginger pair particularly well with sweet potatoes.)  When the sweet potatoes are soft, liquefy them with a stick blender or in the food processor.

Add milk or cream to the mix and you can call your soup bisque.

Throw in some bacon or salt pork and you’re working on chowder.

That’s it.  Simple.

Of course, if you’re like me, you probably appreciate seeing that recipe fleshed out with a few details.

Many of those details are readily available on the web or in cookbooks.  One source I’d particularly recommend is James Peterson’s Splendid Soups.  Peterson is a thoughtful, thorough writer, and I always learn something new from him.  This book will appeal to both beginning and experienced cooks.  One of the recipes in Splendid Soups provided the basis for the soup I present here.

Recipe:  Sweet Potato Soup with Chilies and Corn
(Adapted from James Peterson’s recipe for “Sweet Potato, Chili, and Lime Soup”)

This is an excellent first-course soup:  it entices the palate and stimulates the appetite for dishes to come, but isn’t too heavy.  When you take your first sip of this soup, you’ll notice the sweet potato richness sharpened by chile and citrus highlights.

For this recipe, I suggest a combination of pasilla negro and ancho chile powders.  (For more information about chile powders, read the discussion accompanying my vegetarian chili recipe.  You don’t want to use “chili” powder in this recipe.)  You should be able to find ancho chile powder at many supermarkets.  An online source for both pasilla negro and ancho chile powders is The Chile Shop.  Feel free to substitute combinations of other mild to medium chile powders if you can’t find pasilla negro.

This recipe is best prepared in a 4-quart or larger sauce pan or stock pot.  The recipe yields 6 to 8 servings.  The soup also freezes well.

Ingredients

• 2 tablespoons olive oil
• 2 medium onions (1 ½ - 2 cups) chopped
• salt
• pepper
• 1 carrot peeled and diced
• 2 jalapeno chilies, seeded and finely diced
• 3 cloves garlic, chopped
• 2 pounds sweet potatoes peeled, halved lengthwise, cut into 1/2 inch slices
• 2 teaspoons pasilla negro chile powder (see head note)
• 1 teaspoon ancho chile powder (if you want real kick, substitute chipotle chile powder)
• 4 - 5 cups stock (either homemade or from soup base; turkey, chicken, or vegetable all work well)
• 2 cups frozen corn (may substitute rinsed canned corn)
• juice of 1 lime (or more, to taste)
• plain yogurt for garnish (optional)

Preparation

1. Heat olive oil in sauce pan over medium heat.  When oil is hot (it will shimmer) add onions, season with salt and pepper, and sauté for 5 minutes.
2. Add carrot, jalapeno chilies, and garlic.  Continuing sautéing until onion is soft (about another 3 - 5 minutes; timing is not critical).
3. Add sweet potatoes and chile powders and stir to mix.  Sauté briefly (a minute or so).
4. Add stock.  Bring to a simmer, and cook until sweet potatoes are soft (15-20 minutes).
5. Now it’s time to puree the soup.  If using a stick blender, whirl away in the pot.  If using a food processor or countertop blender, blend in batches so you don’t “blow the top” off your blender (if this happens to you once, you’ll vow never to let it happen again).
6. Add the frozen corn (or drained canned corn if you prefer) and simmer until the corn is just done – about 3 minutes.
7. Add lime juice to taste, stirring to incorporate it into the soup.  The lime is an accent, so don’t add too much at first.  You want to be able to just taste the lime, but don’t want the flavor to dominate.  
8. Serve.  Add a dollop of yogurt as a garnish if you wish.

Notes

Use the stock of your choice.  This soup is particularly good when made with turkey stock, but vegetable stocks are also a hit.  For more information about soup (stock) bases, see Stock Excuses.

This recipe can be prepared ahead through step 5 and refrigerated overnight.  When ready to serve, bring to a simmer and proceed with step 6.

The Sweet Potato Challenge

Are sweet potatoes on your table only once or twice a year for a holiday dinner?  Do you use essentially the same recipe every time you prepare them?

If so, you’re missing out on one of the most versatile and flavorful foods in your supermarket’s produce department.

So seek out a new recipe for sweet potatoes.  (I hope this one appeals to you.)  Try it and I’ll guarantee that you’ll experience a familiar ingredient as if for the first time.

All you have to lose are your marshmallows.