Whisk the cassava flour, ground flax, arrowroot powder, and sea salt together in a large mixing bowl.
Add the oil and work it into the flour until small crumbles start to form.
Gradually add the warm water, a little at a time, and begin kneading into the dough. Add enough water until the dough is moist, but not sticky.
Divide the dough into 8 equal portions and roll into balls. Place each ball between two pieces of parchment paper and use a rolling pin to flatten into thin circular shapes.
Preheat a dry, heavy skillet on the stove over medium-high heat.
Store the tortillas in a covered container in the refrigerator for up to a week.
Notes
Olive oil can be substituted with coconut oil, ghee, or lard.