Congratulations! You are the owner of an ultra-local sourdough starter, or mother, or levain, or any of 100 other names it goes by. I encourage you to name yours. Mine is Shiva. This way, you are more inclined to feel guilt when you neglect it.
To start your culture, take your flakes, crumble them into 100 grams (about ½ cup) warm water. Stir to distribute. Add 100 grams (a scant cup) of flour. Mix and place in a warm spot for 8-12 hours. Maybe you’ll see some activity! Maybe you won’t. Either way, discard most of your mixture, leaving about 25 grams (1Tbsp) and repeat with 100 grams water and flour.
Keep in mind that whole flours are much tastier and more nutritious to wild yeast, so feeding your starter with whole grain flour will accelerate your timing. Repeat this process until your starter is regularly doubling or tripling in size, showing bubbles throughout and smells deliciously tangy.
When it looks happy, bubbly and smells fragrant, a reliable way to test if your starter is ready is the float test. Fill a glass with water, drop in a walnut-size piece of the starter and if it floats or drops to the bottom but rises slowly, it is ready. If it sinks but it has been less than 6 hours, keep waiting. If it sinks and it has been more than 10 or 12 hours, it has gone too far; start over.
To keep your starter alive and well, you’ll need to feed it 1-2 times a week. This is no problem if you’re making bread regularly, as you’ll be using up and replacing it frequently. Keep it stored in your refrigerator until it’s time for feeding, at which point repeat the 25 gram active starter + 100g water + 100g flour.
If you don’t plan to bake regularly, simply work flour into your active starter—no water this time—and rub together until the mixture turns to dry crumbles. Store that in the fridge for up to 3 months; it will take 3-5 feedings for it to be healthy and active again.
Abby (Jane) Love