Sift the flour into a large mixing bowl. Add the salt and warm water. Using a whisk, beat the batter for 5 minutes - or if you're feeling lazy, use an electric whisk for half the time - and keep it up!
In a jug or small bowl, mix together 1 tbsp warm water with the yeast.
Add the yeast mixture to the batter, along with the sugar and baking powder. Once again whisk to combine, this time for around 30 seconds.
Cover the bowl with a clean tea towel and set aside in a warm place for 15-20 minutes until there are bubbles on the surface of the batter.
If you would like to make bacon crumpets, chop the bacon into bite-sized pieces and fry until lightly crisp. Set aside.
Grease the crumpet rings with melted butter and warm a non-stick frying pan over medium-high heat. Grease the pan with a little butter and flavourless oil. Once hot add a ladleful of batter to each ring, reaching around halfway up the ring. It will sizzle on impact and bubbles will form.
If you would like to add bacon, now is the time. Sprinkle a pinch of the cooked bacon pieces over the crumpet batter. Top with a little extra batter.
Keep your eye on the crumpets, and lower the temperature to medium and then to medium-low if you think the pan is getting too hot - you don't want the bases to burn.
Cook for 5 to 10 minutes depending on the heat of the pan. Slowly a skin will form over the surface and bubbles will burst. The centre will take the longest but move the crumpets around a bit so they share the heat and so the bases don't burn.
Once the liquid on the surface has sealed and all the bubbles have formed, you can remove the rings and flip the crumpets to toast the tops. Cook the tops for 30 seconds until lightly golden.
Remove the crumpets from the pan and keep warm in a low oven as you cook the rest of the batter. Serve with your preferred toppings or as an eggs Benedict with poached eggs and hollandaise.