Preheat the oven to 230°C. Put an oven-safe pan in the oven 10 minutes before cooking.
Blend eggs, flour, milk, and salt until smooth and aerated. Let the mixture stand at room temperature.
Chop parsley, mince garlic, and chop 40g of halloumi into a bowl with salt.
Remove the pan, add butter, pour in the batter mix, add cheese and herb mix, then return to oven for 15 minutes.
Slice remaining halloumi and pan fry until golden brown or grill.
Grate a clove of garlic into yoghurt, season with salt and pepper, and mix.
Dress lettuce leaves with olive oil, lemon juice, and za'atar in a bowl. Add red onion, baby tomatoes, and olives to the bowl.
To serve, spoon yoghurt over the Dutch baby base, add the salad, and top with fried or grilled halloumi.
