The Runaway TARDIS
Plorp was the native planet of the Glorp, a friendly race who, according to the Thirteenth Doctor, were fantastic engineers.
The Doctor came to the planet to seek their help in fixing her TARDIS, which was malfunctioning after Lizzie accidentally dropped a peanut butter sandwich into a slot in the control panels. Lizzie befriended the smallest of the Glorp, Blorp, who bonded over their shared love of peanut putter sandwiches, and Lizzie smuggled Blorp home in her rucksack. (The Runaway TARDIS)