• The MasterChef 2020 recap collection: we watch the show so you don't have to

We've come so far, guys. Finals week is next week and tonight Reynold, Laura and Callum are battling it out in the last immunity challenge of the season. It's big, says Reynold, but not big enough for Andy to wear socks again, apparently. He is wearing Meghan Markle's favourite sneakers so I guess that's one step better than Sunday night's Gumby-couture.

Melissa, who is dressed like a sultry snowflake tonight, asks Reynold, Laura and Callum how much things have changed since they were last in this position. Laura feels more confident; Reynold says the best is yet to come; Callum, the ever logical and mathematical nerdy dad, says that he's lived a third of his life since he was on MasterChef last time, and now that he's 30, he finally feels like a real adult.

Melissa says this will be a "battle royale", I hope not like the Japanese horror film where everyone kills each other, or they're going to need to hide the knives. Andy says the first rule of fight club is "there are no rules" – they can cook whatever they want and this is a chance to "bring out every gun they have". Hopefully the contestants have no actual guns, because this is Australia.

Jock says the time limit is up to them – the contestants can choose how long they want to cook for. Reynold wants three hours, but Laura and Callum know that if they give Reynold three hours he will probably build a dessert replica of Melissa or something just as bananas, so they bargain him down to two hours.

Laura thinks she can do this, though she still can't open the pantry door. She says she is making a dish that reminds her of "rocks and pebbles", which, you know, I have never found to be that delicious. She says she wants to bring the judges to a memory from her family beach house, with oyster pebbles filled with muntries and succulents, and a crab "snack" that looks like driftwood. I hope she remembers Harry's epic rock pool failure from back in April, though that episode does feel like seven years ago, so I wouldn't blame her if she had forgotten.

Reynold says he is doing something unique, which is like Poh saying she's run out of time, very unsurprising. He tells Mel he is making one of his hardest desserts, the golden snitch from Harry Potter. Despite J.K. Rowling being cancelled, the dessert sounds great.

He's making a golden sphere out of tonka bean caramel, brown butter mousse and coating it in chocolate, plus honey tuile wings and a pear and yuzu sorbet. Melissa likens winning the golden snitch to winning the golden MasterChef trophy. Yeah but you don't get $250,000 for winning the quidditch world cup, do you?

Meanwhile, in the real world, resident great guy Callum has decided to tug at Jock's French classic heartstrings and make a chicken liver parfait with wattleseed crackers, davidson plum something and onion something. He starts by blending his livers and eggs giving them a "really good whiz up". He says he is happy with how it looks, which is exactly like a McDonald's chocolate thickshake in case you were wondering.

Andy visits Callum and seems about 2 out of 10 enthused about the chicken liver parfait. Jock says there is "nowhere to hide", which is a phrase I can't wait to never hear again when this show is over.

Callum realises he needs to do something special to elevate the parfait, so decides to add bruleed sugar on top. Emelia approves of his brulee technique of melting sugar in the frypan, which means something because she has turned into a French woman in the last few weeks.

Jock and Andy visit Reynold and Jock drops the bombshell that he has never read or watched Harry Potter and doesn't know what the golden snitch even is! Jock, have you been living under Laura's rocks and pebbles?! Even Andy is excited about this concept and turns into a 12-year-old-boy trying to explain the rules of quidditch to a very disinterested Jock.

Andy asks Reynold what could go wrong, because he loves to leave on a negative note, and Reynold says "everything". Luckily one thing has gone right, the MasterChef kitchen just so happens to have intricate wing-shaped silicone moulds in the cupboard perfect for a golden snitch dessert – how convenient!

One hour to go and Laura starts making her oyster emulsion, which will go in her squid ink meringue pebbles. She says she wants the judges to "experience being at the beach", which is very thoughtful now that Melbourne is in lockdown and can't go anywhere. I hope you all have squid ink meringues on your new isolation cooking project lists.

The judges debrief on what everyone is cooking. Jock is happy Laura is going out of her comfort zone (aka: not cooking pasta) and Andy likes that she is cooking from a memory – "bangin", he says, of course.

Jock is concerned about Callum because apparently chicken liver parfait is "every chef's favourite thing to eat", which sounds like a false generalisation, but sure. Of course Melissa is a normal person and has read all the Harry Potter books and seen all the movies. Jock is still confused about the purpose of the snitch and asks if you can eat it. No, silly. You just catch it while flying on broomsticks and win the game even though the rest of your team have been trying to score points with the quaffle. It's very simple, really.

Laura has hollowed out her squid ink meringue pebbles, but when she cuts out circle lids from her meringue shard they crumble, as does her self esteem. She starts panicking and says she needs the discs to prevent the oyster emulsion from spilling out of her pebbles, but there is not enough time to make another meringue sheet.

Everyone's guardian angel Melissa comes over and tells her not to panic. She says if her gut instinct is telling her it's not right, don't waste time and find a new solution. Emelia adds her supportive two cents from the gantry, "come on, mi chiamo", which is an in-joke we will never know.

Reynold dips his mousse spheres into chocolate then sprays it and brushes them with edible gold dust. I mean, if he doesn't win...

At 45 minutes to go, Callum goes into very boring detail about his parfait. It takes him about 15 minutes to essentially say, "I've taken the parfaits out of the oven. I hope they are cooked."

Reece is clapping like a seal and gets offended when the judges laugh at him. "Sorry for trying to be different," he says. We love you, Reece!

Laura has a brainwave and decides to use apple slices instead of her broken meringue shard, which she thinks will balance the saltiness of the shell.

Reynold's hands are shaking as he tries to pull his honey tuiles from the silicone moulds. He snaps the first feather. Then the next one. The gantry are not being helpful, whispering about it on the balcony. "It's an absolute disaster," says Reynold.

There's only 20 minutes to go, and Reynold says if there are no wings there's no snitch. He says he needs a breather and takes a step back from his bench for a quick online meditation session. As he gets back to it, all his feathers magically come out of the moulds perfectly – wow, that fake drama was cruel.

Laura has apparently made a quick trip to St Kilda beach and beachcombed some pebbles and seaweed for her plate. She gets an idea to use sea parsley, a salty parsley, to make a green powder to resemble moss. She pours nitrogen over the parsley to freeze it but keep it vibrant green, again proving that liquid nitrogen is the pantry staple we never knew we needed.

Mel is up on the gantry again because you can't keep a good girl down. Callum is torching his parfait brulee; Laura is tending to her rock garden and making crab sandwiches; Reynold is delicately gluing his snitch wings on.

Time for judging and let's get this over with because Melissa says "bangin" and Andy says "gnarly"; things are getting out of control.

"Cal-diggety-dawg", as Laura calls him, is up first. Andy says this parfait has taken chicken liver parfaits to a new level. "Stop it, Callum," he says, flirtatiously. Jock says it was one of the best he's had, and we know he eats parfait like us regular plebs eat toast. Melissa says the brulee was an extra layer of "fun and frivolity", which is giving a lot of credit to a bit of burnt sugar, but ok!

Laura bring over her beach and Melissa says she's "created a scene". I believe this is a good thing compared to "making a scene". She says it was a "wow" duo of snacks. Andy says it was theatre but she backed up the concept with flavour. Jock says he was transported to the seaside. Will the seaside be enough to beat the quidditch pitch though?

Reynold brings out his snitch. It would not be a Reynold plating without some dramatic liquid nitrogen smoke, so he finishes it with a good cloudy dose of yoghurt snow. The golden snitch is positively glistening, like it was snatched straight from the hands of Draco Malfoy himself.

"Wow, wow, wow," says Jock. Melissa says it's "magic". Jock says he still doesn't know what a snitch is, but it looks pretty good to him. It gets even better: when Jock cuts into the sphere, the tonka bean caramel oozes out. "Stop it," says Andy again.

Melissa says it is a game changer and is "what we live for". Strange priority, but you do you, Mel. Jock says it was "A1, first class" in presentation and flavour and it was the best dish Reynold's ever made. In fairness to Andy, he does give a more eloquent critique than just this usual "bangin" etc (looks like someone has complained to the editors!), even so it was not worth repeating.

The judges say that every dish was great, but Laura and Cal can't beat Reynold. Melissa announces that he has won the first spot in finals week. Reynold pumps the air in pride. Riddikulus!

Read more of our MasterChef recaps here and follow Eloise Basuki on Twitter @eloise_baz.