–Lentils: You can use brown or French Green lentils.
–Broth: Swap chicken broth for vegetable broth.
–Vinegar: lemon juice is a good substitute.
–Seasonings: Adjust to your preference.
Add oil to large skillet and heat on medium
Add diced onions, celery, and carrots and sauté for 10-15 minutes until onions are just barely beginning to brown.
Add garlic and continue to sauté for 1 minute.
Move onion mixture to the sides and add tomato paste. Let it cook for 5 minutes to brown. Stir the tomato paste to prevent it from burning.
Add lentils, broth, diced tomatoes, soy sauce, smoked paprika, cumin, and bay leaf to crock pot.
Add onion/tomato paste mixture. And deglaze with broth.