SERVES: 4 | PREP TIME: 10 minutes | COOK TIME: 3 to 4 hours + 6 to 8 hours if caramelizing the onions
2 or 4 tablespoons bacon fat or coconut oil, melted (see Note)
3 pounds (1.4 kg) onions, sliced
2 cups (480 ml) chicken broth
4 cups (960 ml) beef broth
6 sprigs fresh thyme
3 sprigs fresh rosemary
3 bay leaves
2 teaspoons coarse sea salt, plus more if needed
2 teaspoons freshly ground black pepper
- Grease the inside of a slow cooker with 2 tablespoons of the bacon fat or coconut oil.
- If you’re not caramelizing the onions, skip ahead to the next step. Otherwise, place the onions in the slow cooker and pour the remaining 2 tablespoons of bacon fat or coconut oil over the top of the onions. Cover and cook on high for 6 to 8 hours, stirring every 2 hours while the onions caramelize.
- If you have not caramelized the onions, add the raw onions to the greased slow cooker. Add the chicken broth, beef broth, thyme, rosemary, bay leaves, salt, and pepper and mix well. Cover and cook on high for 3 to 4 hours. Taste the soup and add additional salt to taste if needed. Remove the herbs from the soup before serving.
Note: Caramelizing the onions for this recipe is optional, but it enhances the flavor. If you’re caramelizing them, you will need 4 tablespoons melted bacon fat or coconut oil; if you’re not caramelizing them, 2 tablespoons is sufficient.