Vegetable Focaccia (Tomato, Onion & Herb)

A classic high-hydration focaccia with an open, airy crumb, crispy edges, and a colorful topping of cherry tomatoes, red onion, and fresh rosemary.

Ingredients (one 9×13-inch / quarter-sheet pan)

Dough

• 100 g active sourdough starter (100% hydration)
  or 7 g instant yeast for a non-sourdough version
• 400–420 g water (room temperature)
• 500 g bread flour
• 10 g fine sea salt
• 30–40 g extra-virgin olive oil (plus more for the pan and finishing)

Toppings

• 1–1½ cups mixed cherry tomatoes (red and yellow), halved or left whole
• ½ red onion, thinly sliced into rings
• Fresh rosemary sprigs
• Fresh thyme or oregano (optional)
• Flaky sea salt
• Extra-virgin olive oil
• Optional: a few garlic cloves, black olives, or chili flakes

Instructions

1. Mix the dough
   In a large bowl, mix the starter (or yeast) with the water until mostly dissolved. Add the flour and mix until no dry flour remains. Cover and rest 30–45 minutes.
   Add the salt and 30–40 g olive oil. Pinch and fold until fully incorporated. The dough will be very wet and sticky.
2. Bulk fermentation
   Perform 3–4 sets of stretch-and-folds over the next 2–3 hours (every 30–45 minutes).
   Let the dough continue bulk fermenting until it has risen 50–75% and looks bubbly (usually 4–7 hours total with sourdough, or 1½–2½ hours with commercial yeast).
   For best flavor, you can refrigerate the dough overnight after bulk.
3. Pan & final proof
   Generously oil a 9×13-inch metal baking pan.
   Gently transfer the dough into the pan. With oiled hands, stretch and dimple it toward the corners.
   Cover and let proof until very puffy and jiggly (2–4 hours at room temperature, or longer if the dough was cold).
4. Top the focaccia
   Preheat the oven to 450°F (230°C).
   Dimple the dough deeply with oiled fingers.
   Drizzle generously with olive oil. Press the cherry tomatoes and red onion slices into the dough. Scatter rosemary (and any other herbs) over the top. Sprinkle liberally with flaky sea salt.
5. Bake
   Bake for 25–35 minutes until deep golden brown and crisp on the bottom and edges.
   For extra color, you can broil for the last 1–2 minutes (watch closely).
6. Finish
   Remove from the oven and drizzle with a little more olive oil.
   Cool in the pan for 10 minutes, then transfer to a rack. Best eaten warm the same day.

Tips for success

• High hydration creates the open crumb — resist adding extra flour.
• A metal pan gives the crispiest bottom.
• Salt the tomatoes lightly and pat them dry if they seem very wet.
• Leftovers keep 1–2 days; reheat in a hot oven to restore crispness.

This matches the vegetable focaccia in the photo — golden, dimpled, and loaded with tomatoes, onion, and herbs. Enjoy!