In a large stock pot on medium-high heat, add 2 tablespoons vegetable broth, the chopped onion, and minced garlic. Sauté for 3-5 minutes or until onion is translucent, stirring occasionally.
Add 3 cups vegetable broth (save remaining 1 cup broth for later), 2 cups water, dried lentils, saffron, coriander, cumin, black pepper, salt, and red pepper flakes. Stir over medium-high heat and bring to simmer. Reduce to low heat, cover, and cook until the lentils are no longer firm (12-15 minutes), stirring occasionally. The mixture will thicken up a lot.
*Important note: you can skip this step below (transferring to a blender) if you prefer a chunkier soup.Very carefully pour the lentil mixture into a blender and puree until your desired texture, starting on low power and increasing as you go. If the mixture is too thick, add 1/4 cup water. The more you blend, the smoother the soup will be. If you still want some chunks from the lentils, don’t blend too much- just a few seconds will do. If you want a smoother soup (as shown in the photos), blend for 30 seconds or so. Transfer the mixture back into the large stock pot and add the remaining 1 cup broth and bay leaves; stir. Add the remaining 1/2 cup water now if the soup is too thick. Cook over low heat, uncovered, for about 10 minutes, stirring occasionally. The soup may spatter so make sure it’s on low heat. When ready, remove from heat, then remove the bay leaves. Then add the lemon juice and stir. Enjoy this soup with naan/pita bread and middle eastern garlic sauce.
Storage & Freezing Instructions: Store this soup in the fridge in an airtight container for 4-5 days. The soup will thicken more as it sits, so you may need to add a bit more water or broth before reheating. You can also freeze this soup by placing in an airtight container in the freezer. Let thaw before reheating.