Koimo sweet potatoes are my new love. (If you use the link: the only mention I could find for Koimo sweet potatoes was on Wikipedia. You will need to scroll down to Japan to read about Koimo sweet potatoes.) I bought them at Hmart in Burlington, thinking they would behave like the ordinary orange sweet potatoes we eat raw. The flesh was a creamy white and I expected the same sweet, crisp crunch. Instead, they were hard, starchy and bland. Disappointed, I tucked the rest in the back of my vegetable crisper. One late afternoon while rummaging for dinner possibilities, I decided to roast them. The dense, buttery sweetness was unlike any other sweet potato I have ever eaten. I had prepared a simple lentil dal recipe I adapted from my best Indian cookbook—Indian Home Cooking. 
I roasted some asparagus and mushrooms and served the dal on top of the Koimo sweets. Now it’s all I can think about eating on these cold winter nights.
I invited my friend Heather to lunch, wanting to share this incredible pairing with someone else who gets as excited about food as I do. She writes a wonderful food blog and loves to try new vegetables. We ate in my dining room, talking about our daughters, running, and of course, food. In the end, I sent her a link to the Koimo sweets (because, naturally, I had taken a picture of the display at Hmart.)
and she asked for the lentil dal recipe. The lentil dal is perfect to serve over roasted potatoes of any kind, sweet or not. It is also delicious spooned into half of a roasted squash, or over rice or quinoa. You can tweak the heat up or down, depending on how much spice you enjoy. Here you go, Heather!
Roasted Koimo Sweet Potato with Simple Dal. Roasted Mushrooms and Asparagus for extra beauty and deliciousness.
Simple Lentil Dal with Fresh Ginger, Green Chiles, and Cilantro (adapted from Indian Home Cooking)
Ingredients:
1 c lentils (I use yellow split peas, but you can use red or pink lentils)
1/2 t turmeric
1 t salt
4 c water
Tempering oil:
2 T olive or canola oil
2 t whole cumin seeds
3 whole dried red chiles
1/4 c minced fresh ginger
2-3 T chili garlic sauce (found in the Asian section of any grocery store) OR 2 cloves minced garlic and 1 minced hot green chile
1/4 c fresh chopped cilantro
juice of 1/2 lemon or lime (either is delicious)
Method:
Rinse lentils and put into a large saucepan with the turmeric, salt and water. Bring to a boil and skim well. Reduce heat and simmer until lentils are soft, about 20-25 minutes.
For the tempering oil: Heat the oil with the cumin seeds in s small skillet over medium-high heat. Cook, stirring, until the cumin seeds begin to darken and become fragrant, about 2 minutes. Ad the dried chiles, ginger and chili garlic sauce OR garlic and green chile and cook, stirring, until the ginger softens, about 2-3 minutes. Remove the pan from the heat and add a little water to stop the cooking.
When the lentils are soft, remove from heat. Using an immersion blender, blend until about half of the mixture is smooth. If you don’t have an immersion blender, you can mash the dal with a fork, or puree half in a food processor.
Add the tempering oil, stir, and cook over medium heat for about 5 minutes more. Stir in the cilantro and the juice. Serve hot as is, or over roasted sweet potatoes, potatoes, or grain of your choice with a salad or other green vegetable. This recipe freezes well, so if it turns out that you really like it, double it and save some for a night when there’s no time to cook!
Elizabeth Runs 