Spiralise the sweet potato & cook it in a pan with a little olive oil, salt, pepper & garlic. Cook for 7-8 minutes and transfer to a mixing bowl. Crack 2 eggs into the potato and mix well, ensuring all ‘spirals’ are coated.
Decant the sweet potato mix into 4 ramekins to the half way point and push down with a fork. The ramekins will create the perfect circular bun shape so make sure it’s spread evenly. Place some baking paper on top and a heavy jar or tin of your choice on top of that. Pop into the fridge.
Cook your quinoa as per packet instructions. Chop the coriander leaves & onion and mix in a bowl, add the quinoa once cooked along with the breadcrumbs and the remaining egg. Pour the black beans into a separate bowl and mash with a fork or your fingers. Once mashed, add to the burger mixture. Season with salt & pepper & combine well.
Heat a large griddle pan with some olive oil. With clean hands, scoop a large amount of the burger mixture out (around the size of your palm) and place into the hot oil, using a spatula, press the mixture down. This should create a good sized burger pattie, leave to cook for 2-3 minutes and flip. Repeat this process again for the second burger.
Once the burgers are crispy and fried, transfer onto a plate and remove the sweet potato buns from the fridge. Heat a little oil in the same pan & flip the ramekins quickly onto the griddle (after removing the paper, of course!) The ramekins may need a little tap with the spatula for the mixture to fall onto the pan, you’ll hear it sizzle once it’s out. Leave to cook for 2-3 minutes before flipping, allowing it to solidify.
Once your ‘buns’ are cooked on both sides, arrange on a plate with a crispy iceberg lettuce underneath the burger & a healthy dollop of ketchup. Enjoy!