Heston turns his attention to the much-loved Spaghetti Bolognese. The recipe is broken down and dissected, with versions from the traditional to the radical being tried and tested.

Heston travels to Italy, visiting Naples in order to create the perfect margherita pIzza.

In the first episode, Heston turned his attention to Chicken tikka masala. The search started at his local curry house in Cookham, Berkshire, but soon took him to Delhi where he tried to unravel the complicated roots of this dish. On returning to his restaurant in Bray, Heston tried to build his own tandoor but soon realised that most people aren't able to dig a five-foot-deep hole in the ground and line it with fire bricks. So, he came up with a more accessible solution - a barbecue, but with a few bespoke alterations. In Cambridge, Heston put a chicken breast through a magnetic resonance imaging (MRI) scan to see how a marinade affects the meat as he tried to create the perfect sauce.

Heston Blumenthal went in search of the perfect chilli con carne in last week's programme. He joined the crowds at a chilli cook-off in downtown Washington DC before heading back to Bray to test several types of dried chillies, including Somalian hot and devil's penis chillies, before creating his own spice blend. Heston took one of his chefs for an MRI scan to discover the effect that feeding him chilli oil nine times stronger than any natural chilli has! The ingredients that went into Heston's final dish were whiskey, beef short-ribs and a curious blend of spices, all accompanied by a sour cream sorbet and a sweetcorn muffin.

In the final episode of the series Heston took on the trifle. His journey started with a Bird's trifle. Less than impressed with it, Heston went back to the roots of this dish and visited food historian Ivan Day. Together they made a version of syllabub (the basis of English trifle) by milking a cow straight into a bowl of cider! Ivan explained the evolution of trifle from its 16th century roots through to a dish that we might recognise as trifle.

Celebrity chef Heston Blumenthal attemps to transform some of Britain's favourite dishes, beginning with sausage and mash and treacle tart..

Heston took on a 1970s dessert trolley classic, baked Alaska. His research started at Delmonico's restaurant in New York City, said to be where this dessert was invented. Next his obsession with combining hot and cold in the same dish led him to the work of food scientist Nicolas Kurti, who inspired Peter Barham at Bristol University. Heston and Peter tried to create a hot jam centre - a kind of reversed baked Alaska - to interesting effect. The next challenge was the meringue. The key to perfecting this was finding the type of egg that will give the ultimate insulation for the ice cream inside, so it was back to the lab for some more experiments

In his quest to make the perfect fish & chips, Heston first returns to a childhood haunt - a fish & chip shop in West London - his first time there since age eight. He realizes that the fish & chip culture in England is as much about the ambiance as it is about the food. Not being able to control ambiance, he focuses on the food. For the fish, the travels to Cornwall to test local varieties. His fish of choice, turbot, is an unusual choice and one that offers its own challenges. Because turbot is a flat fish, he has to figure out a batter that cooks as quickly as the thin fish fillet, yet still remains crispy. He turns to the Japanese and tempura for inspiration. For the chips, he ultimately wants to find potatoes that have 22% dry matter, which is the perfect percentage for good textured chips. However, measuring dry matter at home is a virtually impossible proposition, and thus he has to rely on potato variety instead.

Heston took on an Italian favourite - risotto. He visited Gualtieri Marchesi in Lombardy, Italy, whose saffron risotto with gold leaf has earned him three Michelin stars. Then, having paid respects to the old guard, he visited a new-wave Italian chef, Carlo Cracco, who flavours his risottos with some extraordinary ingredients, including instant coffee and anchovies. Heston visited two of Italy's top rice producers, before returning home to decide on what he was going to do with this most simple of dishes - it turns out to be one of his biggest challenges.

Roast chicken to Heston is a family meal and thus holds special meaning for him. The first order of business is to taste test different varietals of chicken to see which is the best as a roast chicken ingredient. The winning bird takes him to Lyon, France, where roast chicken is part of the everyday culture. Eating roast chicken in France also brings him back to memories of childhood. In the four step process to make Heston's perfect roast chicken, he is always taking into consideration the problem of moist meat versus crispy skin, as moist meat is accomplished by cooking at low temperatures, whereas crispy skin is accomplished by cooking at high heat. The final touch in his chicken is injecting the bird with added flavor just before serving. With his roast chicken, Heston makes his traditional vegetable accompaniments of roast potatoes, sautéed carrots and broccoli.