This lentil and red pepper soup is bursting with bell peppers, fire-roasted tomatoes, green lentils, fluffy quinoa, and spinach. Enjoy the flavor of stuffed peppers without all the fuss! This soup is easy to make and ready to eat in less than 1 hour!
When you're in the mood for stuffed peppers but you don't feel like cranking up the oven, roasting the peppers, and making the filling...you gotta try this recipe! It's stuffed peppers in soup form and it's absolutely delicious!
This soup is loaded with red peppers, high-protein green lentils, fluffy quinoa, flavorful fire-roasted tomatoes, and spinach. This recipe is naturally gluten-free and it's ready to eat in less than one hour!
Ingredients & Substitutions
You'll need all of the ingredients in the picture below to make this lentil and red pepper soup. I used a mix of fresh, frozen, and pantry ingredients to make the soup. I listed substitutions below if you need them.
- Quinoa - You could also use brown rice, orzo (not gluten-free), barley (not gluten-free), or cauliflower rice (low-carb).
- Onion - I used a yellow onion, but you could also use a white onion, sweet onion, or shallots.
- Garlic - Fresh garlic gives loads of flavor, but you can sub dried garlic if necessary. Start with 1 tsp and use more to taste.
- Tomato Paste - This is my favorite tomato paste to use because it's organic and in a glass jar.
- Dried Seasonings - Italian seasonings give so much flavor to this soup!
- Canned Tomatoes - I used fire-roasted because it has a smoky flavor, but you can use plain diced tomatoes too. If you use plain tomatoes but still want that smoky flavor, add 1 tsp smoked paprika.
- Bell Peppers - You can use fresh or frozen bell peppers, and any color is fine. I prefer to use red, yellow, or orange peppers because they taste sweeter than green peppers.
- Lentils - You can use dried or canned lentils. Any type of lentils (red, green, black, brown) or legumes (chickpeas, white beans, pinto beans) are fine to use for this soup.
- Maple Syrup - This is used to balance the acidity of the tomatoes. Date syrup or agave can also be used.
- Vegetable Broth - You can sub mushroom broth if you like.
- Greens - I used frozen spinach because it's convenient, but you could also use fresh. Thinly sliced kale, beet greens, swiss chard, or collard greens would all be good options to use.
How to Make It
Start by making the quinoa in a separate medium-sized pot (Photo 1).
While it's cooking, saute the diced onion in a large pot until it's soft and translucent. Add minced garlic, tomato paste, Italian seasonings, salt, and pepper and let it cook for a few more minutes to let the spices flavors bloom (Photos 2-3).
Next, pour in the fire-roasted tomatoes, diced yellow and red peppers, lentils, maple syrup, and vegetable broth to the pot (Photo 4) and bring it to a simmer. Reduce the heat and let it cook until the peppers are tender (Photo 5).
Lastly, stir in the frozen greens and the quinoa and let the soup cook for a few more minutes (Photo 6).
What Goes With It
Serve a bowl of this lentil and red pepper soup with a side of roasted potatoes and a big salad topped with creamy dairy-free ranch. If you like to dip bread into your soup, toasted slices of this no-knead whole wheat bread would be delicious. Any of the following side dishes would be great options too.
Slow Cooker Instructions
If you'd rather set it and forget it, you can also make this lentil and red pepper soup in a slow cooker. Follow these steps:
- Combine the diced onions, garlic, dried seasonings, tomato paste, maple syrup, fire-roasted tomatoes, lentils, red peppers, and vegetable broth in the crockpot.
- You can make the quinoa in the slow cooker or in a separate pot and stir it in later. If you decide to make it in the slow cooker with the rest of the red pepper lentil soup ingredients, you will need to use an additional two cups of vegetable broth or water to make sure it has enough liquid to absorb.
- Set the timer for 3 hours on high.
- After 3 hours, remove the lid and stir in the frozen greens. Put the lid back on and let it cook for 30 more minutes or until you're happy with the texture of the vegetables.
How To Store It
Store leftover soup in an airtight container in the fridge for up to 3 days and you can freeze it for 3 months.
It's best to freeze the soup without the quinoa mixed in so it doesn't absorb all the broth, but you can freeze the soup with everything already mixed together if necessary. The texture will be thicker once you defrost it, but you can use more broth to thin it out.
To defrost the soup, take the container out of the freezer and let it thaw in the fridge for 24 hours. You can then reheat it in a bowl in the microwave or in a saucepan over medium heat on the stovetop until it's warmed through.
Frequently Asked Questions
Yes, you can you use dried lentils. Cook ½ cup in a separate pot and then stir them into the soup. If you want to cook the lentils in the soup, make sure to add 1 extra cup of broth to the soup for the lentils to absorb. I used green lentils, but you could also use red lentils or brown lentils.
If you use canned lentils, you don't need to soak them. If you use dried lentils, I would soak them overnight. Drain and rinse them before using. Soaking the lentils before boiling them is supposed to help with digestion.
I prefer to use to use red, orange, or yellow peppers, because they taste sweeter. You can also use green peppers, but they taste a little less sweet.
- Make the quinoa in a separate pot and only put it in the soup right before you serve it. If you cook it in the soup, it will absorb most of the broth and the texture will be more like a stew.
- Don't drain the juice from the can of fire-roasted tomatoes, it gives a lot of smoky flavor to the broth.
- Put the spinach in at the end so it only cooks for about 5 minutes. By doing this, the leaves will retain their bright green color and it looks prettier in the soup.
Want More Red Bell Pepper Recipes?
- Roasted Veggie Hummus Wraps
- Meatless Sausage & Red Peppers
- Roasted Red Pepper Tomato Soup
- Taco Pasta Salad
Lentil Stuffed Red Pepper Soup
- 6-Quart Dutch Oven of Large Pot
- Medium Pot
- ½ cup quinoa rinsed and drained
- 1 medium yellow onion diced
- 4 medium garlic cloves minced
- 2 tbsp tomato paste
- 1 ½ tbsp Italian seasonings
- ½ tsp salt (more to taste)
- ½ tsp black pepper
- 28 oz can diced fire-roasted tomatoes
- 3 medium bell peppers seeded and diced
- 14 oz can green lentils rinsed and drained
- 1 tbsp maple syrup
- 4 cups low-sodium vegetable broth
- 10 oz bag frozen spinach
- First, make the quinoa in a separate medium-sized pot according to the package instructions. When it's done, take it off the heat and set it aside.
- In a large dutch oven over medium heat, saute the diced onion until it's soft and translucent.
- Add minced garlic, tomato paste, Italian seasonings, salt, and black pepper to the pot. Stir to combine and let it cook for a few minutes to help the flavors meld.
- Next, pour in the fire-roasted diced tomatoes (with the juice), diced bell peppers, green lentils, maple syrup, and vegetable broth to the pot. Stir to combine and increase the heat to bring it to a low simmer. Reduce the heat to medium, and then let the soup cook for 25 minutes.
- Lastly, add the frozen spinach and the quinoa and let it cook for 5 more minutes or until the frozen greens have thawed completely.
- Store the leftovers in an airtight container in the fridge for 3 days or you can freeze it for 3 months.