In a small mixing bowl, combine fresh lemon juice, minced garlic, salt, black pepper, and optional chili flakes. Whisk until well blended, then slowly drizzle in olive oil while whisking until emulsified.

Rinse 1 cup of lentils under cold water. In a saucepan, combine lentils with 3 cups of water and a bay leaf; bring to a boil, reduce to simmer, and cook uncovered for 20-25 minutes until tender.

While lentils are warm, transfer to the saucepan and pour the dressing over. Gently fold lentils with dressing until coated, allow to cool slightly.

Add chopped cucumber, diced bell peppers, and sliced green onions to the lentils. Mix in fresh parsley and mint then fold gently to combine.

Taste and adjust seasonings with salt, pepper, or lemon juice. Serve immediately or refrigerate for at least 30 minutes before serving.