Warm the milk. Since we're using yeast, don't boil the milk. Around 38℃.
Add the flour, yeast, sugar, and salt in a bowl and mix together. Gradually add the milk from Step 1 and continue mixing.
In a different bowl, pour in boiling water. Place the Step 2 bowl over that bowl and cover with a damp kitchen towel for 30 minutes to ferment. When it has doubled in size, it's ready. Stir lightly.
Heat up the unsalted butter in a frying pan. Spread butter on bottomless molds (if available) and pour in the batter. Fry on medium heat until both sides are browned.
Place a thin pat of butter on each crumpet. Pour your choice of sweet sauce on top and enjoy. Serve with a rich milk tea.
You can make them on an electric griddle when you have guests. Just use a small amount of oil, cook both sides, top with butter, and keep warm. You can also make the batter the previous day, refrigerate, and fry the next morning.