½ cup + 1 tablespoon + 1 teaspoon / 137 mlsunsweetened plant-based milk , cold straight from the fridge
1 cup / 218gmashed sweet potato or yam, use orange fleshed sweet potato not white (see notes for how to cook a sweet potato)
2½ cups / 312gall purpose flour(plain flour in the UK) plus some extra for dusting your surface
2tablespoonsbaking powder, aluminum free is recommended
½ a slightly heaping cup / 125gvegan butter, straight from the fridge (plus some extra for greasing the skillet)
2 - 3 tablespoonsmaple syrup (real maple syrup, not pancake syrup), see notes for alternatives
Make sure to keep everything as cold as possible when making this recipe. If you have space, it's good to put the flour in the freezer for 20-30 minutes before you start, but longer is fine. Flour doesn't freeze solid and will stay useable no matter how long you leave it there. Keep the butter, sweet potato and milk in the fridge until the last possible moment too.
Preheat oven to 425°F (218 °C) and have a shelf ready about ¾ way up the oven. Grease a 9-10 inch cast iron skillet really well with vegan butter, or line a baking tray with parchment paper if you don't have a cast iron skillet. Keep the skillet/tray away from the preheating oven so it doesn't get warm.
Whisk the mashed sweet potato with half a cup (120 mls) of the milk and put it in the fridge so it stays nice and cold. Set aside the remaining small amount of milk. you might need it later.
To a food processor or a large bowl, add the flour, baking powder and salt. Pulse or whisk a couple of times to combine.
Add the butter to the flour mixture. Pulse the food processor a few times, or cut the butter in with a pastry cutter or a fork, or by rubbing with the tips of your fingers. Keep going until it looks like breadcrumbs with tiny chunks of butter throughout. See my picture in the post above for a guide. In a food processor it will likely only need 3 or 4 pulses. Don't over process it. It's the little butter chunks that make the biscuits flaky.
Take the milky sweet potato mixture out of the fridge and pour it into the food processor/bowl. Pulse a few times to combine or mix gently. If it's a little too dry, add the remaining milk that you set aside earlier very gradually. Pulsing in between until when you touch the dough it feels like it will come together easily. Remove the blade, ball up the dough and wrap in cling wrap. Place in the fridge for 10 minutes while you clean up the mess you made so far and clean your work surface.
Dust the work surface with a generous sprinkle of flour. Remove the dough from the fridge. Unwrap it and roll it out gently into rough rectangle-like shape about 1/2 an inch thick. Dust the top with a little flour as needed to stop the rolling pin sticking and don't be too fussy about the shape. Gently fold one half of the rectangle into the centre, and then the other side too, a bit like an envelope. Check my pictures in the post for a visual guide. Then roll it back out and fold in the same way again. Do this a total of 4 times. It's important not to skip this as it is what creates the layers in the biscuits. Work as quickly as you can and touch the dough as minimally as you can with your hands to help keep it cool.
Once you're done with the folding, use your hands to pat it out to an even 1 inch thick and use a metal 3 inch cutter or a glass to cut the biscuit shapes. Do not twist the cutter. Use a straight up down motion and keep the cuts close to get as many as you can out of the dough. The first rolled batch is always the best so we want to limit how much dough is left.
Gently transfer the cut biscuits to the greased skillet/lined baking tray, then gather up the remaining dough into a ball and gently pat out to 1 inch thick again. Cut as many biscuits as you can out of it, probably only another 1 or 2, or until you have 8 biscuits.
I don't like to waste anything, so pat the remaining scrap of dough into a rough round shape and get it ready on a separate baking tray to put in the oven when the rest go in. That one's for you. Eat it as soon as it comes out of the oven. You earned it ;O)
Brush the top of each biscuit generously with maple syrup and put them in the oven. Cook for 18 to 20 minutes or until well risen and golden. Be sure not to open the door while they are baking as it will affect the rise.
Remove from the oven and enjoy warm. Store leftovers in an airtight container.
I recommend reading my success tips in the post above for some really helpful tips about making this recipe successfully. For brushing the tops of the biscuits prior to baking, maple syrup gives the best results both looks and flavour-wise. If you don't have any though, you can use a little extra milk or aquafaba (liquid from a can of chickpeas). For tips on freezing and reheating see the post above. Jump there by clicking here.
HOW TO COOK SWEET POTATO
I found that 1 large sweet potato made enough mashed potato for this recipe. Have a spare one on hand just in case though. Once it is cooked and cooled, peel off the skin and mash it really well with a fork. If you are in a hurry you can mash it while it's hot and spread the mashed sweet potato out on a cold plate to cool it quickly. To microwaveI find the easiest way to cook the sweet potato is in the microwave. Pierce all over then place on a piece of kitchen paper or a plate and cook on high until soft. It takes about 5-7 minutes.In the ovenPierce the potato a few times with a fork or knife, and place on a baking tray in an oven that has been preheated to 425°F (218 °C). It will take roughly 45 - 50 minutes although it will vary depending on size so check by piercing with a knife or fork. It will be tender when done.In an Instant Pot Set the potato on the trivet in the bottom of the Instant Pot. Pour in 1 cup of water. Put the lid on and cook for around 22 minutes high pressure with a natural pressure release.