Preheat the oven to 200°C.
Rinse the lentils thoroughly then put them in a saucepan. Cover completely with cold water and cook until soft. It takes about 15-20 minutes.
In the meantime, cut the vegetables into 5 cm pieces, arrange them a baking tray, drizzle with the the oil, then sprinkle with the chilli flakes. Roast for about 20-30 minutes, until soft and golden brown.
Dry-fry the nuts. Let them cool then roughly chop.
Grate the lemon rind, mix with the nuts and parsley.
Drain the cooked lentils and mix them with the roasted vegetables. Season with salt & pepper, add the lemon juice.
Just before serving, add the nut mixture and toss well.