Rinse the oat groats thoroughly under cool running water, then place them in a clean glass jar.

Cover the groats with about 2-3 inches of water, secure the lid with a sprouting screen or cheesecloth, and let them soak for 8-12 hours at room temperature.

Drain the water completely, rinse the groats thoroughly with fresh cool water, and then drain again, ensuring no standing water remains.

Invert the jar and prop it at an angle to allow air circulation and continued draining, repeating the rinsing and draining process every 8-12 hours for 5-7 days until sprouts are 1/2 to 1 inch long.

Once the sprouts reach the desired length, give them a final rinse and drain, then store them in an airtight container in the refrigerator for up to a week.