Thomas's Milkshake Muddle

S9, E3: It’s the day of the Sodor Summer Party, Thomas is sent to collect milk and butter. On his return, Thomas goes too fast and turns the milk half-way to butter. Thomas puffs back to the dairy to collect more milk, this time very slowly. By now, Thomas is late for his second job, but has an idea... by puffing fast with the half-churned butter, he makes enough butter for all the cakes!