It's the final week of the heats and six more professional chefs from across the UK head into the MasterChef kitchen determined to show the judges they have star cooking quality.The first challenge to test their mettle is the infamous skills test. Under close scrutiny from Monica, Marcus and Gregg, the chefs have their skills, knowledge and confidence put to the test. The first skills test has been set by Marcus. The chefs have to roll, form and fill pasta to make a dish of pork-filled ravioli with a chasseur sauce. The judges look out for classic culinary knowledge and the ability to create depth of flavour in the accompanying sauce. There is a wide range of talents the chefs can either show off or stumble at in this 20-minute introduction to the MasterChef kitchen.For the next three chefs, Monica has chosen the famous oyster rockefeller as her test. This buttery, herb-crusted, baked shellfish dish has been around in many forms for over a century, but the chefs won't get very far if they don't have the knack for shucking the oyster at the off.All six chefs are invited back in to the MasterChef kitchen for the next nerve-racking round. This is their chance to really show off with their signature dish. Cooking a tried-and-tested dish for Monica, Marcus and Gregg, any chefs that lost face in the last round can turn their fate around. In an hour and 15 minutes, their future is decided as the judges send three chefs home and settle on which three go through to this week's quarter-final.