Cook the lentils: In a medium pot, combine rinsed lentils, water or broth, and the bay leaf. Bring to a boil, then reduce to a gentle simmer. Cook uncovered for 18–25 minutes until tender but not mushy. Drain well, discard the bay leaf, and spread the lentils on a sheet pan to cool quickly.

Prep the vegetables and herbs: While the lentils cook, halve the tomatoes, dice the cucumber, and finely chop the onion. Chop the parsley, mint, and any optional dill or basil. Keep the herbs fairly coarse so they stay fresh-looking.

Make the dressing: In a small bowl or jar, whisk together olive oil, lemon juice, lemon zest, Dijon, garlic, salt, and pepper until emulsified.

Toss while warm: Add the warm (not hot) lentils to a large bowl. Pour in about two-thirds of the dressing and toss gently. Warm lentils absorb flavor better, which builds a deeper taste.

Add crunch and color: Fold in tomatoes, cucumber, and onion. Add the chopped herbs and the remaining dressing. Toss again and taste. Adjust salt, pepper, or lemon as needed.

Rest and serve: Let the salad stand for 10–15 minutes at room temperature so the flavors meld. Finish with a drizzle of olive oil and a pinch of flaky salt if you like. Serve slightly warm or chilled.

Optional add-ins: Sprinkle in crumbled feta, a spoonful of capers, chopped olives, toasted nuts, or a handful of arugula just before serving for extra texture and richness.