Autolyse: Mix flour, milk, honey, and sourdough starter. Rest 40 minutes.
Mix & Knead: Add egg yolk and salt. Knead 5–10 minutes. Slowly add melted butter. Continue kneading until smooth and elastic.
Bulk Ferment: Ferment 4–6 hours at room temp. Do stretch & folds every 30 minutes for the first 2 hours. Refrigerate 8–12 hours.
Shape: Divide dough into 80–100 g pieces. Roll into long ropes. Shape into pretzels.
Final Proof: Let rest 2 hours, until puffy.
Baking Soda Bath: Boil 1 L water + 30–40 g baking soda. Dip each pretzel 15 seconds. Place on baking sheet and sprinkle coarse salt.
Bake: Bake at 200–210°C / 392–410°F for 15–18 minutes, until golden brown.
Serve: Best warm with cheese dip, mustard, or garlic butter.