Winter squashes are the perfect base for a winter soup--but they can tend to taste alike. I, at least, find it challenging to make them distinctive no matter what additional ingredients I add.
But when I came across kaffir limes at the Schaner Farm's booth at the Little Italy Mercato last week, I knew I had a match in the making. There's no disguising the powerful, astringent aroma and flavor of kaffir limes. In fact, you have to have a restrained hand to ensure that they don't overtake whatever else they're paired with. Kaffir limes are beloved in Southeast Asian and Thai cuisine. You'll find the leaves and zest used in soups, curries and curry pastes. Pair with ginger, lemongrass, coconut milk, and other regional ingredients to get the most out of them.
At home I had an unusual looking grey kabocha squash I'd gotten at OB People's Co-op. So, on a rainy evening I took a look around and pulled out a yellow onion, jalapeño peppers from my garden, garlic, chicken stock, fish sauce, spiced vinegar (easy to find at 99 Ranch Market and other Asian markets), and a chunk of ginger. I wish I'd had lemongrass and coconut milk, but no--and I wasn't about to go out in a big storm--so I made do.
The result was a thick, fragrant soup redolent of ginger and kaffir lime. Not too much. Just enough to give the mellow squash a terrific ping of flavor. A warming, spicy soup for a rain-soaked February night.
Grey Kabocha Squash Soup with Kaffir Lime and Ginger
Makes 10 cups
1, 3-pound Grey Kabocha squash (or other hard winter squash), peeled, seeded (keep the seeds), and cut into one-inch pieces
1 medium onion, peeled and diced
3 jalapeño peppers, diced
2-inch chunk of fresh ginger, peeled and grated
4 cloves garlic, minced
2 tablespoons canola or other vegetable oil
1 kaffir lime, zested and then juiced (save the juice)
32 ounces of chicken stock or broth
1 tablespoon fish sauce
2 tablespoons spiced vinegar (available at Asian markets)
salt to taste
1. Heat oil in a large pot and add onions. Saute until translucent, then add garlic, ginger, and jalapeños. Saute another couple of minutes.
2. Add squash chunks, half the kaffir lime zest, stock, fish sauce, and vinegar. Bring to a boil.
3. Reduce heat, cover the pot, and simmer for an hour.
4. Remove from heat. Puree in the pot with a stick blender or carefully transfer to a blender to puree. Add the rest of the kaffir lime zest and all the lime juice. Add salt to taste.
P.S. I always save the seeds from winter squash to toast. Just put them in a colander and rinse/pull the fibers off, dry the seeds, toss with oil and salt, then roast at 300 for about 15 minutes. (Check on them frequently; they can burn in a heartbeat)