Vegetarian 15-Bean Soup

Ingredients

• 1 (20 ounce) package 15-bean soup mix (seasoning packet not used)
• 2 tablespoons olive oil, or more as needed
• 1 large onion, diced
• 12 carrots, peeled and chopped, or more to taste
• 15 crimini mushrooms, sliced, or more to taste
• 7 stalks celery, chopped, or more to taste
• 6 leaves dinosaur kale, chopped
• 4 leaves red Swiss chard, chopped
• 3 large cloves garlic, minced
• 12 cups vegetable broth
• 2 bay leaves
• 1 teaspoon dried rosemary
• 1 teaspoon dried basil
• Salt and ground black pepper to taste

Directions

Place beans in a large container and cover with several inches of cool water; let stand 8 hours to overnight. Drain and rinse.

Heat olive oil in a stockpot over medium heat; cook and stir onion until golden brown, 15 to 20 minutes. Add carrots, mushrooms, celery, kale, chard, and garlic; cook and stir until carrots and mushrooms are slightly tender, 5 to 10 minutes.

Pour broth over vegetable mixture and bring to a boil; reduce heat and add bay leaves, rosemary, basil, salt, and pepper. Add beans and simmer soup until beans are softened, 1 1/2 to 2 hours.