1. 1. Assessing Your Sourdough Starter’s Activity: Before you even mix your dough, ensure your sourdough starter is active and bubbly. Feed it 4-12 hours before you plan to mix, and it should double in size and pass the float test (a small dollop floats in water). If your starter isn’t active, your dough won’t rise properly, leading to under-proofed bagels.

2. 2. Monitoring Bulk Fermentation (First Rise): After mixing your dough, allow it to undergo bulk fermentation. Look for a noticeable increase in volume, typically 30-50%. The dough should feel airy and slightly jiggly. If it’s not rising enough, your kitchen might be too cold; try moving it to a warmer spot or using a proofing box. If it’s rising too quickly and becoming overly bubbly and slack, it might be too warm, indicating potential over-proofing.

3. 3. Shaping and The Finger Dent Test: Once shaped into bagels, they need a second proof. The “finger dent test” is crucial here. Gently press a floured finger into the side of a bagel. If the indentation springs back immediately, it’s under-proofed. If it stays indented and doesn’t spring back at all, it’s likely over-proofed. The ideal is a slow spring-back, leaving a slight indentation.

4. 4. Observing Cold Proofing in the Refrigerator: Cold proofing slows down fermentation, developing flavor and making the bagels easier to handle. After cold proofing (usually 12-24 hours), your bagels should look slightly puffy but not overly expanded. They should feel firm but still have some give. If they are very slack and spread out, they might have over-proofed in the fridge due to a too-warm refrigerator or too long a proof.

5. 5. The Float Test for Proofed Bagels: A reliable way to check if your shaped bagels are ready for boiling is the float test. Drop a bagel into a bowl of cool water. If it floats within 10-20 seconds, it’s perfectly proofed and ready to boil. If it sinks, it’s under-proofed and needs more time. If it floats immediately and looks very airy, it might be slightly over-proofed, but still salvageable.

6. 6. Boiling and Baking Cues: When boiling, perfectly proofed bagels will puff up slightly and maintain their shape. If they collapse or wrinkle, they were likely over-proofed. During baking, a well-proofed bagel will brown evenly and develop a beautiful crust. Under-proofed bagels might be dense, while over-proofed ones can be flatter and less chewy.