Get the gluten-free sourdough starter recipe here
Preheat the oven to 350F / 180C. Blend the scallion, olive oil, water, sweet potato and salt until creamy.
Transfer the blender content to a mixing bowl and add the sourdough discard, psyllium husk, and caraway seeds and combine with a spatula.
Gradually add the cassava flour and combine (use your hands when it is getting solid). Gently knead and portion into two equal parts, which you will shape into balls.
Place a piece of parchment paper on a working surface, place the dough on top, and shape it into a rectangle with your hands. Add another piece of parchment paper on top and roll out with a rolling pin to about 1/12 inch or 2mm thickness.
Gently peel the top paper off and slide the bottom paper with the crackers onto a baking sheet. Portion into small rectangles or squares with a pizza cutter and prick the crackers with a fork. Optionally, sprinkle with sea salt flakes.
Bake for about 15-20 minutes. Keep an eye on them starting at 15 minutes. If, after 20 minutes, they are not crispy, turn the oven heat off, and let the door semi-open with the crackers inside for about 10 minutes. Once done, put the heat back on to prepare for the second batch.
Store these crackers at room temperature in a glass container with a lid. They will stay crispy.