Long-Fermented Spelt Sourdough Tray Pizza Party

Instructions

Steps show original quantities. Use the adjusted ingredient list for your batch; times stay unchanged.

1. Refresh 30 g refrigerated starter with 60 g white spelt flour and 60 g water. Once active, expand toward approximately 500 g levain with 175 g water and 175 g flour. Use 500 g mature, bubbly levain for the dough; a levain that has peaked and begun to recede slightly is acceptable.

2. For easier KitchenAid mixing, divide the dough into two identical batches. For each batch use:

   • 1000 g white spelt flour
   • 250 g strong bread flour
   • 937.5 g water
   • 250 g active levain
   • 27.5 g salt
   • 50 g olive oil

3. For each KitchenAid batch, combine 937.5 g water and 250 g levain, then add 1000 g white spelt flour and 250 g bread flour. Mix with the dough hook on low speed for 2–3 minutes, until shaggy. Rest 20 minutes.

4. Add 27.5 g salt and 50 g olive oil to each batch. Mix on KitchenAid speed 2 for about 3–4 minutes, stopping once cohesive, soft, and somewhat elastic. Do not chase a full windowpane or overwork the spelt.

5. Combine the two mixed batches on a lightly wetted counter for one lamination: gently stretch into a broad sheet without tearing, then fold left and right toward the center and fold again to make a package. Rest 20–30 minutes, then perform one gentle stretch-and-fold.

6. Divide the dough between two lightly oiled, covered tubs and refrigerate for about three days of cold bulk fermentation, such as Tuesday to Friday.

7. The evening before serving, preheat the par-bake oven to maximum heat, above 250°C if available, using the bottom-heating-element-plus-fan mode (fan symbol with a line beneath it).

8. Work from each tub in thirds to make six pizzas total. For each tray, spread approximately 3 tbsp olive oil over the entire tray, including corners. Lightly oil hands, gently pull approximately one-third of a tub into the tray, and separate cleanly without aggressively degassing.

9. Let each portion rest about 15 minutes. Gently press outward from the top with fingertips. Rest another 10–15 minutes, then finish stretching, including gently lifting from underneath and allowing gravity to help. Avoid forceful pulling.

10. If using sesame edges, after the final stretch lightly oil the outer edge, sprinkle with lightly toasted sesame seeds, and press them very gently into the dough.

11. Cover the tray dough while it finishes proofing so the surface does not dry. Judge readiness by a soft, slightly puffy dough with visible bubbles rather than by the clock alone.

12. Par-bake one tray at a time in the bottom-heat-plus-fan oven on a lower-third rack. Start checking around 6 minutes; aim for roughly 6–8 minutes, adjusting to the oven. The top should remain pale, the bottom only lightly golden, and the crust should be structurally set but still flexible.

13. After each par-bake, wait about 20–30 seconds, then immediately loosen the perimeter and underside with a thin spatula and confirm the crust releases from the tray. Transfer to a cooling rack rather than allowing it to cool stuck in the tray.

14. Cool every par-baked crust completely and uncovered. For overnight holding, place parchment between cooled crusts and stack carefully, rotating successive rectangular crusts 90 degrees where useful to avoid crushing. Never stack or wrap them while warm.

15. For the sauce, combine:

    • 1200 g Mutti crushed tomatoes
    • 60 g tomato paste or concentrate
    • 20 g salt
    • 30 g olive oil
    • optionally 1 tsp dried oregano

    Do not cook the sauce.

16. Drain 1500 g baby mozzarella, halve or quarter it as appropriate, spread it on towels, and dry thoroughly before topping. Plan about 250 g mozzarella per pizza.

17. For cheese pizza, spread about 250 g dried mozzarella over a par-baked crust, then spoon approximately 180–220 g uncooked tomato sauce over the cheese. The cheese-first, sauce-second order helps protect the par-baked crust from tomato moisture.

18. For pepperoni pizza, add about 250 g dried mozzarella and 180–220 g sauce, then arrange pepperoni generously in a regular grid designed around the planned slice lines so each piece receives pepperoni and the cutter can pass between slices.

19. For Kalamata and red-onion pizza, add about 250 g dried mozzarella and 180–220 g sauce, then scatter halved Kalamata olives and very thinly sliced red onion evenly.

20. For the final bake, heat both ovens to maximum with convection/fan. Start each pizza in its tin tray on a middle rack and bake about 5–8 minutes, checking early because the crust is already par-baked. Look for fully melted, bubbling cheese, browned spots, crisp edges, and a properly reheated base.

21. For additional bottom crispness, remove the whole tray to the counter, slide the pizza safely onto a waiting rack, then return the pizza directly to an oven rack for approximately 60–90 seconds if needed. This counter transfer is safer and loses less oven heat than trying to transfer the pizza inside an open oven.

22. Finish as desired with finely grated Parmesan and fresh basil, then cut and serve.

Success cues

• After bulk fermentation the dough is aerated and extensible but still holds structure rather than becoming slack and soupy.
• Tray dough stretches progressively after rests without needing force and retains visible gas.
• Par-baked crust has a pale top, a barely/lightly golden underside, and remains flexible rather than crisp.
• Par-baked crust releases from the oiled tray shortly after baking.
• Fully cooled par-baked crusts can be held overnight with parchment between them without trapped condensation.
• Finished pizza has a crisp, olive-oil-fried bottom, airy thin focaccia-style crumb, melted cheese, and no soggy center.

Scaling notes

• Mix the full dough in two batches; the 1875 g water total divides into 937.5 g per batch. The 500 g levain in the dough comes from the preceding build, not an additional purchase.
• Keep tray oil at approximately 3 tbsp per tray; change the number of trays rather than multiplying the per-tray quantity. Tray dimensions remain unknown, so judge dough coverage and thickness.
• Use about 250 g mozzarella and 180–220 g sauce per pizza. The sauce batch may leave a small surplus. Adjust unmeasured toppings by coverage; keep one tray per oven for consistent par-baking.

Storage

• For overnight par-baked crust storage, cool completely uncovered before stacking or covering.
• Separate cooled par-baked crusts with parchment; do not trap steam from warm crusts.
• Do not leave par-baked crusts stuck in their tins while cooling; loosen and rack them promptly.

Substitutions

• The dough intentionally uses 80% white spelt flour and 20% strong bread flour for strong structure while keeping the pizza predominantly spelt.
• Optional toasted sesame can be applied to the outer crust edge before par-baking.