6 tablespoons / 90mlsaquafaba, (the liquid from a can of chickpeas)
360 mls / 1½cupswater
oil for pan, mild olive oil, vegetable oil or sunflower oil. Melted refined coconut oil is also ok but do not use virgin or unrefined coconut oil.
Preheat oven to 425°F (218 °C) and have a shelf set about 3/4 way up with an old baking tray on it. It must be preheated with the oven and is there to catch any oil spillovers when you are cooking the puddings.
In a medium bowl, add the all purpose flour, chickpea flour, baking powder and salt and whisk them together. As I mention in my post, I highly recommend weighing the ingredients for optimum results.
In a jug, combine the mustard, apple cider vinegar, aquafaba and water and whisk them together.
Pour the combined liquids into the dry ingredients and whisk together until smooth and bubbly. Pour into a jug to make pouring quick and easy, then leave to rest for 10 minutes.
While the batter is resting, prepare your muffin pans. They must be metal pans and not ceramic and they must be muffin pans and not shallow Yorkshire pudding pans. If you use a pan with shallow wells they will not work. Add enough oil to give a depth of about 3mm, then swirl it around in the pan so it goes up the sides. For my muffin pans that is about 1¼ tablespoons for each well. Don't be tempted to use less as the batter won't get hot enough when you pour it in and that will mean that you won't get nice bowl shaped Yorkshire Puddings. Put the oiled muffin pans in the oven for 10 minutes. By then they should be absolutely smoking hot. That's what you want. If you don't see smoke rising from them if you open the door to peek, leave them a minute or two longer.
You need to work very quickly now. Make sure your jug of batter is right next to you as you open the oven. Very quickly, but very carefully, remove the muffin pan from the oven, making sure to close the door to keep the heat in. In a long, thin stream, pour the batter into the hot oil in each well of the pan. You need to fill them nearly to the top. The oil will rise above the batter (that's what makes gives you the bowl shape puddings). Stop pouring once the oil is just about level with the rim of the well. You need to do this really quickly because you need to keep the heat in the pan for the puddings to work well. As soon as the wells are all full, put the pan right back into the oven and shut the door quickly. You should get 6 to 8 Yorkshire Puddings from the batter.
Cook the puddings for at least 30 minutes, but maybe up to 35 or 40 minutes until really golden and crispy and until the insides have dried out to your liking. I like them a little gooey inside and 30 minutes will get them there. If you prefer them a little dryer, turn the oven down and let them cook a little longer. Do not open the oven door, not even for a quick peek until you are past 25 minutes of cooking.
Remove the puddings from the oven and serve immediately.
For gluten-free Yorkshire Puddings, omit the all purpose flour and use a total of 150g (scant 1⅓ cups) chickpea flour. Or, with thanks to reader Jennie for trying this, use 25g each mix of corn starch (cornflour in the UK), potato flour and tapioca flour in place of the 75g all purpose flour. She says they work perfectly like that. You must follow this recipe exactly. There can be no substitutions at all, except maybe mustard for kala namak which I suggest above. Everything else must remain the same. Believe me, I have tried every combination of ingredients and methods possible, and to get the best result you cannot change a thing.As stated in my post, when making these Vegan Yorkshire Puddings, you need to use a metal muffin pan or a popover pan. Both have deep wells. A traditional shallow Yorkshire Pudding pan will not work and any pan that is not metal will not work.If you have leftover puddings, they can be refrigerated and reheated in a hot oven (425°F/218 °C) for 3 to 4 minutes until hot. They can also be frozen. Reheat them straight for the freezer on 425°F/218 °C for 10 minutes.