Golden Turmeric Potato and Spinach Casserole (غراتان سیب‌زمینی و اسفناج) — Mediterranean-Inspired Layered Gratin

• 900 gYukon Gold potatoes, peeled and cut into 3 cm chunks
• 2000 mlWater (For boiling)
• 10 gFine salt (5 g for potato water + 5 g for seasoning)
• 45 mlExtra-virgin olive oil (For mashing and richness)
• 2 gBlack pepper, freshly ground
• 20 mlLemon juice, freshly squeezed (Brightens the mash)
• 180 gYellow onion, finely diced
• 12 gGarlic cloves, minced
• 2 tspGround turmeric (About 6 g)
• 400 gFresh spinach, roughly chopped (Washed and well-drained)
• 150 gSalami or ham, diced (Choose beef or turkey for halal)
• 200 gMozzarella cheese, shredded (Low-moisture mozzarella melts best)

Instructions

1. 1

   Preheat the oven to 200°C and set a rack in the middle. Lightly grease a 23×33 cm baking dish with 10 ml olive oil, making sure the corners are coated so the gratin releases cleanly.

2. 2

   Add the potatoes, 2000 ml water, and 5 g of the salt to a pot and bring to a steady boil. Cook for 15–18 minutes until the potatoes are very tender and a knife slides through without resistance, then drain thoroughly and return them to the hot pot for 1 minute to steam off excess moisture.

3. 3

   Mash the hot potatoes with 45 ml olive oil, 20 ml lemon juice, 5 g salt, and 2 g black pepper until smooth and creamy. If the mash feels wet, keep mashing over low heat for 30–60 seconds to evaporate moisture, because a drier mash bakes into cleaner layers.

4. 4

   Warm 30 ml olive oil in a wide skillet over medium heat, then add the diced onion and cook for 6–8 minutes until soft and lightly golden. Stir in the minced garlic and cook for 30 seconds, keeping the heat moderate so the garlic turns fragrant without browning.

5. 5

   Add the turmeric to the onion-garlic base and stir for 20–30 seconds to bloom the spice in the oil. Immediately add the spinach in batches, tossing until fully wilted and the pan is mostly dry, about 4–6 minutes, because excess liquid can make the casserole watery.

6. 6

   Stir the diced salami or ham into the spinach mixture and cook for 1 minute to warm it through and distribute its savory flavor. Turn off the heat and let the filling cool for 3 minutes so it does not melt the cheese prematurely during assembly.

7. 7

   Spread half of the mashed potatoes evenly in the prepared baking dish, pressing gently to create a level base. Spoon the turmeric spinach mixture over the potatoes in an even layer, then sprinkle 120 g of the mozzarella across the surface for a cohesive, melty center.

8. 8

   Dollop the remaining mashed potatoes over the cheese and gently spread to seal the filling, smoothing the top with a spatula. Scatter the remaining 80 g mozzarella over the top so it bakes into a golden, stretchy crust.

9. 9

   Bake for 20–25 minutes until the cheese is deeply melted and the edges are bubbling. For extra color, broil for 1–2 minutes at the end while watching closely, then rest the casserole for 10 minutes so the layers set before slicing.