Rinse lentils thoroughly under cold water. In a medium saucepan, combine the rinsed lentils, 3 cups of water or vegetable broth, and 1/2 tsp salt. Bring to a boil, then reduce heat to low, cover, and simmer for 20-25 minutes, or until lentils are tender but still hold their shape.

Drain any excess liquid from the cooked lentils and set them aside to cool slightly.

Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper.

On the prepared baking sheet, toss the halved cherry tomatoes with 1 tbsp olive oil, dried oregano, 1/4 tsp salt, and 1/8 tsp black pepper. Spread them in a single layer.

Roast for 15-20 minutes, or until the tomatoes are slightly softened and beginning to burst. Remove from oven and set aside to cool.

In a small bowl, whisk together the extra virgin olive oil, red wine vinegar, Dijon mustard, minced garlic, chopped fresh parsley, chopped fresh mint (if using), 1/2 tsp salt, and 1/4 tsp black pepper until well combined.

In a large mixing bowl, combine the cooled cooked lentils, roasted tomatoes, diced red onion, diced English cucumber, and diced red bell pepper (if using).

Pour the prepared dressing over the lentil mixture and gently toss to combine, ensuring all ingredients are well coated.

Taste and adjust seasoning if needed. Serve immediately or chill for at least 30 minutes for flavors to meld.