In a bowl, mix pumpkin purée, sourdough discard, egg yolk, salt, and nutmeg.
200 g pumpkin purée, 1 egg yolk, ½ tsp salt, ¼ tsp nutmeg, 30 –40g sourdough discard
Stir in potato flakes and let sit for 5 minutes to hydrate.
30 g potato flakes
Gradually add the flour mix (00 + AP) and gently fold until a soft, slightly sticky dough forms. Avoid overmixing!
100 g 00 flour, 100 g all-purpose flour
Transfer to a lightly floured surface and knead just until smooth (about 30 seconds to 1 minute).
Wrap the dough in parchment/plastic wrap and refrigerate for 12–24 hours to cold ferment.