Day #1: Add to a clean mason jar 2 tbsp of flour of brown rice or sorghum flour and 2 tbsp of filtered tap water. Mix the flour and water together to make a thick but stirrable slurry. Cover the jar with a coffee filter and secure it with a rubber band and place the jar in a warm place in your house.
Days #2-6: Feed your starter twice per day. I typically feed it in the morning when I wake up, and again before bed. To feed it, discard half of the starter from the jar. Add 2 tablespoons of water and 2 tablespoons of flour. Mix it together, scrape down the sides, then cover it and allow it to do its magic on your countertop at room temperature. As you continue to feed the starter, you'll see it rise (almost double in size) then fall after feeding it. This is normal and good.
Day #7: By day seven, the starter should be bubbly and airy. This means you're almost ready to bake! Take a whiff. Do you smell that tangy, sour aroma? Can you hear it bubbling? If so, it's ready as it has fermented nicely. If not, continue to feed it twice daily for a few more days, and make sure you're storing it in a warm place so the yeast and bacteria can do their magic.
Notes
Once the sourdough starter is ready, you can measure out what you need, then place the starter in your fridge and feed it once per week. It should last for years if you feed it weekly. When you're ready to bake bread, take out what you need from the jar, feed it, and bring it to room temperature (3-4 hours or overnight) before using.You can use any gluten-free flour for the sourdough starter. I have used brown rice flour and sorghum flour and both work well. Make sure your flour is labeled gluten free.You do not have to discard half of the starter each day. Doing so will speed up the ferment process; however, if you're okay to go slow with it, you can simply feed the starter without discarding any of it. I typically discard starter for the first 7-10 days, then just feed the starter daily from there on out without discarding any of it. After you have developed your starter, you can store it in your fridge and feed it once per week. Mark your calendar so you don't forget to feed it!If you see murky water pool on top, it means your starter is hungry. Feed it! Once you make your sourdough starter, you're ready to bake some bread. Here is my artisan gluten-free sourdough bread recipe.