By Marie Bozer, Senior Services Dietetic Intern from Central Michigan University
Who are the three sisters? They’re not really a who, but more of a what. The three sisters are crops native to North America and traditionally grown together by various indigenous peoples including the Iroquois, one of the native peoples of present day Michigan. The three sisters are corn, squash, and beans.
Why were they grown together? Companion planting at its finest. When grown together, the three sisters not only enrich the soil they are grown in, but support each other’s growth as well. Vining, low-growing squash covers the ground and acts as a weed barrier for the corn and beans. Squash’s ground cover also protects the soil from drying out in the summer sun, keeping it cool and moist. Some squash varieties have prickly leaves and help deter pests like racoons too! Beans are a nitrogen fixing plant; they take nitrogen out of the air and sequester it in the ground, providing an essential nutrient to the squash and corn. This is especially great for the corn, which is a notoriously heavy feeder. Corn provides support to the beans, which have shallow roots. The corn grows tall giving pole beans something to climb on!
The three sisters not only grow well together but also provide complementary nutrition when eaten together. Corn, a whole grain, is rich in B vitamins, magnesium and manganese. Beans are a good source of protein and packed with fiber. Squash is a great source of potassium and vitamin A. Different kinds of beans and squash will have differing amounts of each individual nutrient. Even sweet corn and popping corn have different amounts of nutrients!
There are many different ways to cook with and enjoy the three sisters. Beans can be refried, made into a soup, hidden in a brownie, and make nutritious additions to pasta and salads. Squash can be roasted, mashed, and put in soups and stews. Pumpkin puree can be added to oatmeal with pie spice. Acorn and delicata squash make a hearty side dish when stuffed. Corn can be popped. Corn tortillas make flavorful taco shells. Hominy can be added to soups and stews. Polenta, similar to grits, is popular in Italian cuisine. If you are watching your salt or fat intake, making popcorn at home or baking corn tortillas to make home-made tortilla chips can be a great way to reduce salt and fat intake.
As the weather warms and gardens are planned, consider adding the three sisters to your garden this spring.
Three Sisters Casserole
Serves 8, Prep Time: 35 minutes, Cook Time: 25 minutes, Total Time: 60 minutes
For the cornbread topping:
- 1 1/4 cups yellow cornmeal
- 1/2 cup all-purpose flour (or your favorite all-purpose gluten-free flour blend)
- 2 teaspoons baking powder
- 1 teaspoon kosher salt
- 2 tablespoons unsalted butter, melted
- 1/2 cup whole milk
- 1/2 cup water
For the filling:
- 3 tablespoons extra virgin olive oil
- 1 yellow onion, diced (about 1 cup)
- 4 cloves garlic, minced
- 1 pound butternut or kabocha squash, peeled and cut into 1-inch cubes (about 2 cups)
- 1 (15-ounce) can diced fire-roasted tomatoes
- 2 tablespoons tomato paste
- 1 teaspoon ground coriander
- 1 1/2 teaspoons ground cumin
- 1/2 teaspoon chili powder
- 1/4 teaspoon smoked paprika
- 1/2 teaspoon kosher salt
- 3/4 cup vegetable broth
- 1 cup fresh or frozen corn kernels
- 1 (15-ounce) can kidney beans, rinsed and drained
- 2 cups chopped greens (such as spinach or kale)
- Preheat the oven to 350°F: Spray a 9×13-inch baking dish with non-stick cooking spray and set aside.
- Make the filling: In a large, high-sided skillet or Dutch oven, warm the olive oil over medium heat until it’s shimmering and add the onions. Cook until translucent, about 4 to 5 minutes. Add the garlic and cook for an additional minute. Add the squash, tomatoes, tomato paste, spices, and salt. Stir in the broth and bring mixture to a boil.
- Simmer the filling: Cover the pot and reduce heat to low. Simmer for 15 to 18 minutes, or until squash is tender.
- Make the cornbread topping while the filling simmers: In a medium mixing bowl, whisk together cornmeal, flour, baking powder, and salt. Using a wooden spoon, slowly stir in the butter, milk, and water; mix only until just combined. Set aside and let it sit for ten minutes or so, while the filling simmers.
- Add the rest of the ingredients to the filling: Stir in the corn, beans, and greens into the filling, and continue cooking, covered, for 3 to 5 minutes, until mixture has thickened slightly and all the ingredients are incorporated.
- Transfer to baking dish and bake: Scrape the filling into the prepared pan and top with generous biscuit-sized clumps of cornbread topping (this can be rustic and uneven). Bake for 20 to 25 minutes, or until filling is bubbling and topping is golden brown.
- Serve: Remove from the oven allow to cool for 5-10 minutes before serving.
About the Author: Marie Bozer is a life-long resident of Midland, MI. She graduated from Midland High School in 2006 and is currently pursuing a career in Dietetics. Marie is enrolled in the CMU Dietetic Internship and will finish this program in April 2022. After her internship Marie plans to pass the Registered Dietitian Exam and find employment in the field she loves.