To a large pot or dutch oven, warm up the olive oil then add coarsely chopped onion, celery, and carrot, and fry on medium heat for 5 minutes stirring often.
Add grated garlic and cumin and fry for one more minute, or until you smell their aroma.
Add vegetable broth, canned tomatoes, dried lentils, thyme, oregano, salt, pepper, or/and red pepper flakes.Cover with a lid, bring to a boil, then crack the top open and simmer on low heat for about 25 minutes or until the lentils are cooked but still al dente. Stir occasionally.
OPTIONAL STEP: if you like extra creamy soup, blend about 2 cups of it. You can do this with an immersion blender directly in the pot, or with a regular blender.
Add the spinach and simmer for a few more minutes until they wilt and you are happy with the texture and consistency of the soup/lentils.
Taste and adjust for salt. Serve it in a bowl with a slice of toasted bread rubbed with garlic and a drizzle of good quality extra virgin olive oil. Optionally, you can add a squeeze of lemon juice.
Nutritional information is an estimate for 1 serving of lentil vegetable soup out of 4 servings, without bread or toppings.SUBSTITUTIONS- Dried lentils: substitute drained and rinse canned lentils but add them in the soup 15 minutes after the broth and tomatoes start simmering. Canned lentils can only take about 1o to 15 minutes of simmering before falling apart. You can also use canned beans or chickpeas.- Olive oil: substitute any vegetable oil or coconut oil for olive oil.- Onion: substitute leek or shallots for onions. - Herbs: you can use fresh or dried herbs. Substitute rosemary and bay leaves for thyme and oregano.- Spinach: you can use most leafy greens including curly kale, lacinato kale, Swiss chard, bok choi, and more. You can even add vegetables such as diced potatoes, diced sweet potatoes, bell peppers, mushrooms, cauliflower and broccoli florets. If you add veggies, do so at the beginning, with the dried lentils so that they have time to cook fully.TOPPINGSYou can top this lentil vegetable soup with homemade croutons, crostini, grated parmesan cheese, crumbled feta cheese, dairy-free cheese, lemon zest, lemon juice, and drizzle of good quality EVO oil, chopped parsley.MAKE AHEAD & STORAGE- Make Ahead: this lentil vegetable soup is an excellent recipe to make ahead as you can refrigerate it for several days or freeze it for months. Also, on the second and third days, the soup tastes better than when it's freshly made because the flavors have time to meld.- Refrigerator: let the soup cool down completely at room temperature, then transfer it into an airtight container and keep it in the fridge for up to 4 days.- Freezer: let the soup cool down completely at room temperature, then transfer it into a freezer-friendly container and freeze for up to 3 months.- Thaw: thaw in the refrigerator over several hours or in the microwave with a thawing function.- Reheat: you can reheat the soup in a pot on the stovetop for a few minutes or in the microwave for 2 to 3 minutes. Avoid reheating it multiple times.