In a large pot, heat olive oil over medium heat. Add diced onion and minced garlic, sauté for 3-4 minutes until the onion is translucent.

Incorporate diced carrots, chopped celery, and diced red bell pepper. Sauté for an additional 5 minutes until softened.

Pour in vegetable broth and add rinsed lentils. Bring to a boil, then reduce heat, cover, and simmer for 15 minutes.

Stir in drained chickpeas, drained black beans, thyme, basil, and salt and pepper. Continue simmering uncovered for another 10 minutes.

Add chopped kale, green beans, and frozen peas. Cook for 5-7 minutes until greens are wilted.

Remove from heat and stir in lemon juice and chopped parsley. Adjust seasoning as needed.

Ladle soup into bowls and garnish with extra parsley. Serve warm.