Rinse the lentils under cold water, ensuring they are clean. Combine them with 4 cups of water in a medium saucepan. Boil on high heat, then reduce to a simmer for 20-25 minutes until they’re tender but still hold their shape. Drain and set aside to cool.

Whisk together the dressing in a small bowl: combine olive oil, fresh lemon juice, cumin, salt, and black pepper. Whisk until all ingredients are well blended and smooth.

Mix the cooled lentils with the chopped parsley, red onion, cherry tomatoes, and diced cucumber in a large mixing bowl. Ensure everything is well distributed for a colorful bite.

Pour the dressing over the lentil mixture and toss gently to combine, being careful not to mash the lentils or vegetables.

Chill the salad in the refrigerator for at least 30 minutes to allow the flavors to meld beautifully. Optionally sprinkle with feta just before serving for an extra creamy touch.