4 tablespoons melted lard, bacon grease, or coconut oil (lard is traditional)
1 teaspoon sea salt
2 cups (plus more, as needed) whole wheat flour (hard wheat is better than soft as it contains a bit more gluten and holds together better when rolling out)
Combine starter, milk, salt, and melted fat in a medium bowl. Stir in flour, 1/2 cup at a time, until you hit two cups.
At this point determine whether your dough needs more flour. You are looking for a dough that is slightly sticky, but not so moist that it is messy. You will be kneading on a floured surface so don’t add too much flour.
Add flour until desired texture is achieved. Plop out onto a floured surface and knead for about three minutes.
Cover and place in a warm location in your kitchen for 8 to 24 hours to ferment.
When ready to cook tortillas divide dough into eight pieces. Roll each into a small ball and place back into covered bowl. Remove balls from container one at a time and roll them out on a floured work surface until desired thickness is reached.
Carefully transfer tortilla to a hot griddle that has been heating over medium-high heat. Cook for about 30 seconds, or until bubbles begin to form and the edges firm up.
Flip and finish cooking another 30 seconds.
Serve hot or cool and store to eat for a few days. The sourdough helps to keep the tortillas soft and fresh for a longer time than non-sourdough tortillas.