Dan Buettner is the Blue Zones Founder, National Geographic Fellow, New York Times bestselling author, and producer of Emmy Award-Winning: "Live to 100" Series. He's made it his mission to teach people how to embrace the blue zones’ way of life and live to a healthy 100. Food is an important part of the equation, obviously, and many recipes like this one can be found on his website. 

If you want a spicier stew, you can use a hot chili powder or even pure ancho chile powder. For a mild option, he recommends trying sweet smoked paprika.

• 1 (28-ounce) can crushed tomatoes, preferably fire-roasted tomatoes (about 3 1⁄2 cups)
• 3 cups cooked and drained black beans, such as Rancho Gordo Midnight Black beans
• 1 cup cooked and drained red beans, such as Rancho Gordo Domingo Rojo beans 
• 2 cups vegetable broth
• 2 medium sweet potatoes (about 1 1⁄4 pounds total weight), peeled and cut into cubes
  
• 1 medium yellow or white onion, chopped (about 1 cup)
• 2 medium red potatoes (about 12 ounces total weight), cut into cubes
• 2 tablespoons minced garlic
• 2 teaspoons chili powder
• 1 teaspoon ground cumin
• 1⁄2 teaspoon salt
• 1 cored and diced red bell pepper, for garnish
• Finely chopped scallions, for garnish
• Finely chopped fresh cilantro leaves, for garnish

Serves 6

1. In a 5- to 6-quart slow cooker, combine the tomatoes, black beans, red beans, broth, sweet potatoes, onion, red potatoes, garlic, chili powder, cumin, and salt .
2. Cover and cook on high for 4 hours or on low for 8 hours.
3. Ladle into bowls and garnish with bell pepper, scallions, and cilantro.