Simon Hopkinson is the culinary world's big secret. His book Roast Chicken and Other Stories, was voted "the most useful cookery book of all time" by his peers, beating the combined output of Delia Smith, Rick Stein, Nigel Slater, Hugh Fearnley-Whittingstall and others, even though the book is 15 years old.

Waitrose Food Illustrated magazine in the UK, which compiled the poll, described Hopkinson as "having an amazing ability to write recipes for the home cook that are accessible, practical and sensible, but still challenging enough to be exciting".

And now he has turned his attention to cooking without meat or fish for his new book, The Vegetarian Option.

Vegetables feature strongly, but there are plenty of original ideas and yummy recipes for pasta, rice, eggs and fruit. Macaroni cheese with tomatoes is the perfect comfort food for rainy winter nights, and spinach mousse with parmesan cream is already gaining cult status among food bloggers.

Thyme, Onion and Gruyère Tart

Serves 4-6

For the pastry:
65g cold butter, cut into cubes
100g plain flour
Pinch of salt
1-2tbsp iced water

For the filling:
50g butter
750g white onions, peeled and very thinly sliced
1 large egg
2 large egg yolks
200ml double cream
2tsp Dijon mustard
1tsp thyme leaves
Salt and freshly ground white pepper
60g Gruyère, freshly grated
Freshly grated nutmeg

* To make the pastry, briefly process the butter, flour and salt together in a large food processor until the mixture resembles fine breadcrumbs.

* Now tip into a large, roomy bowl and gently mix in the water with cool hands or a table knife, until well mixed. Knead the dough lightly, then put into a plastic bag and chill in the fridge for at least one hour before rolling.

* For the filling, melt the butter in a wide, shallow pan. Tip in the onions and very gently sweat over a moderate heat for at least 40 minutes, or as long as one hour, until pale and golden and completely soft. Cool.

* Meanwhile, preheat the oven to 180ºC/gas mark 4, and place a flat baking sheet inside to heat (it will help the base of the tart to cook thoroughly).

* Roll out the pastry on a lightly floured surface as thinly as you dare, then use to line a 20cm tart tin, 3cm deep. Prick the base with a fork. Line the pastry case with foil and dried beans, slide onto the hot baking tray and bake 'blind' for about 15-20 minutes.

* Remove the foil and beans and return the pastry case to the oven for a further 10 minutes or so, until it is golden, crisp and well cooked through, particularly the base.

* Mix together the egg, egg yolks, cream, mustard and thyme leaves. Carefully mix in the onions, season and pile the mixture into the pastry case. ?Sprinkle the Gruyère over the surface and generously grate over some nutmeg. ?Bake in the oven for about 45 minutes, or until the filling is a rich golden colour and just firm to touch. Leave to stand for 10 minutes before eating.

Spinach mousse with Parmesan cream

Serves 4

For the mousse:
A little softened butter
250g spinach leaves
2 large eggs
225ml double cream
Salt and freshly ground white pepper
Freshly grated nutmeg

For the Parmesan cream:
250ml whipping cream
40-50g Parmesan, freshly grated
Salt and freshly ground white pepper

* Preheat the oven to 180ºC/ gas mark 4. Butter the base of each of four buttered dariole moulds or ramekins and line with a tiny disc of greaseproof paper. Blanch the spinach in boiling water for one-two minutes. Drain and refresh under very cold running water, then squeeze in a tea towel until completely dry. (You should have approximately 120g cooked weight of spinach.)

* Purée the eggs and spinach in a blender until really smooth. Pour into a bowl, stir in the cream until well mixed and season with a little salt, pepper and nutmeg. Pour the mixture into the prepared moulds filling them to the brim.

* Cover each with a round of foil and place in a deep baking dish. Pour tap-hot water into the dish until it comes at least three-quarters of the way up the sides of the moulds. Bake in the oven for 20-25 minutes, or until firm to touch.

* To make the Parmesan cream, pour the cream into a saucepan and whisk in 40g of the Parmesan. Bring to a simmer and allow to gently bubble for a few minutes, whisking occasionally. Taste the sauce and add more cheese if you think it needs it, maybe a little salt, but definitely grind in some pepper. Simmer until of a suitable coating consistency.

* Once the mousses are cooked, turn them out onto warmed plates and spoon over the Parmesan cream. Serve promptly.

Orange Brûlée

Serves 4

Finely pared zest of 1 large orange (no pith whatsoever)
125g caster sugar
400ml freshly squeezed orange juice, strained
6 large egg yolks
200g crème fraiche

* Using a small food processor, grind together the orange zest and 75g of the sugar, until you have a bright orange paste. Put the orange juice into a stainless-steel pan, add the orange zest paste, bring up to a simmer and reduce by half, to about 225 ml. Put to one side to cool for 15 minutes.

* Whisk the egg yolks and crème fraiche together in a bowl, then whisk in the reduced orange mixture. Return to the pan and cook very gently over a low heat until thickened to custard-like consistency. Take care to avoid overcooking, but make sure the custard is cooked enough, otherwise it will not be firm enough, once cold; you can safely take it as far as the odd blip, and when this happens, whisk vigorously to disperse the hotspots.

* Strain the custard immediately into four ramekins and cool completely, then chill in the fridge for at least six hours, preferably overnight.

* Sprinkle the remaining sugar over the surface of the custards and caramelise under a preheated hot grill, or using a cook's blow-torch, until melted, golden and blistered in parts. Chill once more for an hour.

* Serve the brûlées very cold. Eat with small teaspoons.

The Vegetarian Option by Simon Hopkinson is published by Quadrille Publishing, priced stg£20