Crumble the cheese and marinate in the juice and zest of half the lemon, half the olive oil and the dried mint.
Put the lentils in a large saucepan of water and add the onion, garlic and chilli oil. Bring to the boil and simmer for about 25 minutes until just tender. You want the lentils to retain some bite. Drain.
Tip the lentils into a bowl and pour over the remaining olive oil. Season with salt and add the remaining lemon zest and juice. Drain the peppers and mix into the lentils carefully.
When the salad has reached room temperature add the cheese and sprinkle over the fresh mint to serve.