Mystery Box Challenge: For the mystery box challenge, the contestants must cook their signature burger. The top three dishes were Avery's, Zac's, and Kya's. Kya wins the first Mystery Box challenge.
Challenge Winner/Immune: Kya Lau
Elimination Challenge: Kya is safe from elimination and gets to enjoy a cake made by Christina. Kya can also select a second contestant to be immune from elimination. She picks Vivian. The cooks learn marshmallows will be the star ingredient in their next dishes. The judges call up Addison, Ian, Kade, Sam, Jesse, and Alexander. Sam, Jesse, and Addison are deemed to have the best dishes of the night, leaving Alexander, Kade, and Ian as the bottom three.
Immune: Vivian Stich
Winners: Addison Osta Smith, Jesse Gunn and Sam Sy
Bottom three: Alexander Cochran, Ian Marcel Sanders and Kade Dugas
Ian is sent to safety, eliminating both Alexander and Kade.
Individual Challenge: Sam, Jesse, and Addison compete against one another in a cupcake-frosting race. They have ten minutes to frost as many cupcakes as perfectly as Christina demonstrates. The winner will get immunity from elimination and the losers will have to press a giant button that unleashes a large amount of frosting on whichever judge the kid is paired with. Addison gets Gordon, Sam is with Graham, and Jesse is with Christina. The judges invite MasterChef Junior season 2 winner Logan Guleff to officiate this round. Sam and his twenty-nine perfectly frosted cupcakes beat Jesse's eleven cupcakes and Addison's ten which means Sam wins immunity and Graham will get no frosting on him. Gordon and Christina get their frosting shower, then the contestants have a frosting food fight.
Challenge Winner/Immune: Sam Sy
Elimination Challenge: The kids have one hour to come up with a scallop dish, but the contestants will have to shuck the scallops themselves. Gordon gives a quick shucking lesson and then sends the kids off to create a dish. Tae-Ho is declared the winner of this elimination test. Kamilly, Chad, Annabelle, and Vivian are announced as the bottom four.
Winner: Tae-Ho Ahn
Bottom four: Annabelle Nolan, Chad Gibbs, Kamilly Serrano and Vivian Stich
Kamilly and Vivian are sent to safety, eliminating Chad and Annabelle.
Mystery Box Challenge: For the mystery box challenge, the contestants are required to create a dish using various types of cheese. The top three dishes were Addison's, Kaitlyn's, and JJ's. Kaitlyn was announced as the winner of the Mystery Box.
Challenge Winner/Immune: Kaitlyn Tomeny
Elimination Challenge: Kaitlyn is safe from elimination. The rest of the contestants are required to create a delicious fish dish using various types of fish. After shown how to filet a giant moonfish by Graham, the cooks have to pick which fish to be used for their dishes. Kaitlyn can also select a second contestant to be immune from elimination. She picks Addison. Among the contestants, Avery picked halibut, Jesse picked mackerel, Nate picked yellowtail, while Vivian, Jaeclyn and Sam all picked Thai snapper, and lastly Kya picked salmon. The best fish dish of the night belonged to Nate. Vivian, Kyndall and Jaeclyn, were called down to the front for having the worst three fish dishes of the night.
Immune: Addison Osta Smith
Winner: Nate Murwaski
Bottom three: Jaeclyn Clark, Kyndall Latson and Vivian Stich
Jaeclyn was sent to safety, resulting in the elimination of both Vivian and Kyndall.
Team Challenge: The home cooks were split into three teams and they must compete to see which team can create a seven layer dip in a relay challenge, with the winning team getting to dunk that judge's head in the dip. Ian's team has Zac, Amaya, JJ, Jesse, and Mia. Avery's team has Kaitlyn, Tae-Ho, Derek, Adam, and Jaeclyn, while Kya's team has Addison, Sam, Kamilly, Corey, and Nate. Ian's team wins.
Team Challenge Winners/Immune: Amaya Baéz, Ian Marcel Sanders, Jesse Gunn, JJ O'Day, Mia Wistwostika and Zac Kara
Elimination Challenge: Ian, Amaya, Jesse, JJ, Mia and Zac are immune from elimination. They also get to select which selection of ingredients the remaining contestants must cook in the upcoming challenge. The team selected Graham's "smelly" ingredients. Addison had the best dish, followed by Nate. The worst three dishes belonged to Corey, Jaeclyn and Adam.
Winners: Addison Osta Smith and Nate Murwaski
Bottom three: Adam Queens, Corey Gifft and Jaeclyn Clark
Team Challenge: The cooks will be split into two teams where they will be serving party food to a group of young kids in a birthday lunch party. Addison and Nate will be team captains. For her Blue Team, Addison picked Kya, Mia, Kaitlyn, Corey, Zac, Kamilly and Tae-Ho, while for his Red Team, Nate picked Derek, Sam, JJ, Amaya, Jesse, Avery, and was left with Ian. The Blue Team won the challenge.
Team Challenge Winners/Immune: Addison Osta Smith, Corey Gifft, Kaitlyn Tomeny, Kamilly Serrano, Kya Lau, Mia Wistwostika, Tae-Ho Ahn and Zac Kara
Pressure Test: The Red Team will have to create a croquembouche. Amaya, Derek, Ian and Nate were left to have the worst croquembouches of the challenge.
Bottom four: Amaya Baéz, Derek Quinn, Ian Marcel Sanders and Nate Murwaski
Amaya and Ian were judged to have just done enough to be sent to safety, eliminating Nate and Derek.
Team Challenge: The remaining chefs are split into two teams; the Red Team consists of Avery, Kya, JJ, Sam, Kamilly, Jesse, and Ian while the Blue Team has Addison, Zac, Amaya, Kaitlyn, Corey, Mia, and Tae-Ho. Each team has seven minutes to make a glass of raspberry mint lemonade and serve it to Christina for a blind tasting. Christina declared the Red team as the winner of the challenge.
Team Challenge Winners/Immune: Avery Kyle, Ian Marcel Sanders, Jesse Gunn, JJ O'Day, Kamilly Serrano, Kya Lau and Sam Sy
Elimination Test: The remaining cooks are tasked to make a lobster and steak dish in 60 minutes. Kaitlyn was declared as the winner, while the worst three dishes of the night belonged to Tae-Ho, Mia and Corey.
Winner: Kaitlyn Tomeny
Bottom three: Corey Gifft, Mia Wistwostika and Tae-Ho Ahn
Corey's dish was deemed the best of the worst and he was sent to safety, eliminating Tae-Ho and Mia.
Mystery Box Challenge: The home cooks will be tasting a dish made by Gordon Ramsay while blindfolded, and then tasked to replicate it in one hour. Kya and Kaitlyn win the challenge.
Challenge Winners: Kaitlyn Tomeny and Kya Lau
Elimination Test: This will be a team challenge, where the home cooks need to serve 31 dishes using ingredients from New England or New Mexico in 90 minutes. Kya and Kaitlyn will be team captains for this challenge, Kya chose to select the ingredients first and chose the crate from New England. Kaitlyn picked Addison, Zac, Kamilly, JJ and Amaya for the Blue Team, while Kya chose Avery, Sam, Corey, Jesse and Ian for the Red Team. The Blue Team was the winner. Kya, Corey, Jesse, and Ian will face elimination.
Challenge Winners: Addison Osta Smith, Amaya Baéz, JJ O'Day, Kaitlyn Tomeny, Kamilly Serrano and Zac Kara
Bottom four: Corey Gifft, Kya Lau, Ian Marcel Sanders and Jesse Gunn
Team Challenge: Only four kids will get to compete for immunity in the Elimination Test. Zac and Kamilly form the Red Team, while Kya and Amaya form the Blue Team. The two teams will make the most correctly cooked deviled eggs in twelve minutes, and the winning them will be safe from the upcoming elimination challenge. Gordon Ramsay and Graham Elliot are the Yellow Team, and if Gordon and Graham win the challenge, all home cooks will have to compete in the upcoming elimination challenge. Zac and Kamilly are the winners.
Team Challenge Winners/Immune: Kamilly Serrano and Zac Kara
Elimination Test: The contestants were asked to do one signature recipe. Avery and Amaya have the best dishes of the night. The bottom three were Corey, Addison, and Kaitlyn.
Winners: Amaya Baéz and Avery Kyle
Bottom three: Corey Gifft, Kaitlyn Tomeny and Addison Osta Smith
Addison was sent to safety, leading to the elimination of Corey and Kaitlyn.
Mystery Box Challenge: The kids will have 60 minutes to make any dish they want using the Mystery Box ingredients. The best three dishes were Addison's, Zac's, and Sam's. Zac was declared as the winner of the Mystery Box.
Challenge Winner: Zac Kara
Elimination Test: The kids will be put into four teams of two, and only one of them can cook at a time. Every ten minutes, the judges will call for a switch, and the other teammate will pick up where the first left off. The teams will have to cook five different types of street food from around the world. Zac gets to select his teammate and pair up the other contestants. He picks Kya as his teammate, and pairs Sam and Kamilly, Addison and Amaya, and JJ and Avery. Amaya and Addison were the winners of the challenge. Zac, Kya, Sam, and Kamilly are at the bottom.
Team Challenge Winners: Addison Osta Smith and Amaya Baéz
Bottom four: Kamilly Serrano, Kya Lau, Sam Sy and Zac Kara
Team Challenge: The contestants will be split into two teams, chosen by Addison and Amaya, and are responsible for feeding twenty of Gordon's friends. Addison picks Kya and JJ for her Blue Team, while Amaya picks Zac and Avery for her Red Team. The Red Team wins.
Team Challenge Winners: Amaya Baéz, Avery Kyle and Zac Kara
Bottom three: Addison Osta Smith, JJ O'Day and Kya Lau
The judges send Addison to safety, eliminating JJ and Kya.
Mystery Box Challenge: The contestants reunite with their parents. They must create a soufflé for the final Mystery Box Challenge. The judges pick Addison's soufflé.
Challenge Winner: Addison Osta Smith
Elimination Test: Addison gets to decide who gets which cut of various pork products. Zac gets pig's ears, Addison wants the ribs for herself, and Avery gets the pork belly, which leaves Amaya with the loin. Avery has the best dish and is a finalist.
Winner: Avery Kyle
The judges then announce Addison as the second finalist, eliminating Amaya and Zac.
Season Finale: The judges want the finalists to prepare and present a three-course meal – appetizer, entrée, and dessert.
Appetizer: Addison makes a sake marinated shrimp with seaweed and sea bean salad, sour plums, and puffed rice salad. Avery makes a cream of asparagus soup with smoked oysters, crème fraiche, and creole crouton
Entrée: Addison makes a miso black cod with bok choy, shiitake mushrooms, and coconut ginger broth. Avery makes a seafood étouffée with crispy okra and white rice.
Dessert: Addison makes a green tea panna cotta with cookie crumbles and brûléed plums. Avery makes strawberry shortcake with rhubarb and orange chantilly cream.
Final Two: Addison Osta Smith and Avery Kyle
Winner Announced: Addison is announced as the fourth MasterChef Junior winner, taking home the trophy and the $100,000 prize. In addition, Addison became the youngest overall winner.
