Warm the olive oil in a dutch oven or large pot over medium heat. Add the diced onion and sauté for 2 to 3 minutes until softened. Add the sliced carrots and celery, sauté for an additional 1 minute. Stir in the tomato paste to coat the vegetables evenly. Continue sautéing for 2 to 3 minutes, stirring occasionally to develop flavor.

Add the minced garlic, Italian seasoning, paprika, cumin, bay leaves, and black pepper to the pot. Mix everything well and cook for 1 minute to toast the spices, releasing their aroma and enhancing the depth of the soup.

Pour in the rinsed green lentils, crushed tomatoes, vegetable broth, and 3 cups of water. Stir to combine all ingredients. Bring the mixture to a vigorous boil over high heat, then reduce to medium heat to let it simmer gently. Cook uncovered for 20 to 30 minutes, stirring occasionally, until the lentils are tender. If the soup becomes too thick, add the remaining 1 cup of water to achieve desired consistency.

Remove and discard the bay leaves from the soup. Stir in the fresh lemon juice to brighten the flavors. Taste and adjust seasoning with salt and pepper as needed.

Ladle the warm soup into bowls and garnish with chopped fresh parsley. Enjoy immediately or store leftovers in an airtight container in the refrigerator for up to 5 days, or freeze for up to 2 months for later enjoyment.