Heat your oven to 200°C/Fan 180°C/Gas 6. Peel and trim the parsnips. Cut them into quarters lengthways. Place on a baking tray. Whisk 2 tsp honey with 2 tsp oil. Drizzle over the parsnips and season with salt and pepper.
Wrap 1 garlic clove in a square of foil and nestle next to the parsnips. Slide into the oven and roast for 30 mins, till the parsnips are soft and golden. Flip the parsnips over halfway through cooking.
While the parsnips roast, tip the couscous into a bowl. Pour in 125ml boiling water and add a pinch of salt. Set aside, covered with a plate, so the couscous can absorb the water.
Add the pumpkin seeds to a medium pan and toast over a medium-low heat for 2-3 mins till nutty. Tip into a food processor. Strip the kale leaves from their cores. Add to the processor. Blitz till the ingredients form a paste. Zest and juice in half the lemon. Season. Slowly trickle in 4-6 tbsp cold water till you get a pesto-like paste. Don't have a food processor? See our tip at the end for what to do instead.
Peel and finely chop the onion. Finely chop the carrot and celery. Peel and grate or crush the 2 remaining garlic cloves. Finely chop the rosemary leaves.
Heat 1 tsp oil in a pan. Add the chopped onion, carrot and celery. Cook for 5 mins over a medium heat till softened. Add the grated or crushed garlic and cook for 1 min. Add the rosemary and cook for 1 min more.
Drain and rinse the lentils. Add them to the pan and warm through, stirring, for 5 mins. Unwrap the roast garlic clove and press down on it with a fork to squeeze it from its skin. Stir the garlic into the kale pesto. Add more lemon juice if you think it needs it.
Fold the couscous through the lentils. Pile onto warmed plates. Top with the honeyed parsnips. Serve with the kale pesto.