Prepare your spinach. Place the thawed spinach in a clean tea towel or a few layers of kitchen paper. Twist and squeeze firmly over the sink until almost no liquid comes out. You should have a dry, dark green clump. This step is crucial – excess water will make your dip watery later.

Sweat the aromatics. In a large frying pan or skillet, melt the butter over a medium heat. Once it's foaming and smells nutty, add the diced onion. Cook, stirring occasionally, for 4-5 minutes until the onion becomes translucent and softens, releasing a sweet, mellow scent. Add the minced garlic and cook for just 30 seconds more, until fragrant but not browned.

Build the creamy base. Reduce the heat to low. Add the softened cream cheese to the pan, breaking it up with a wooden spoon. Stir continuously as it melts into the onion and butter, creating a thick, pale yellow sauce. The texture will be smooth and glossy. Now, stir in the sour cream and mayonnaise until fully combined. You'll see the mixture turn a uniform, pale ivory colour.

Incorporate the greens and artichokes. Add the squeezed-dry spinach and the chopped artichoke hearts to the pan. Stir everything together gently but thoroughly. The deep green of the spinach will streak through the creamy sauce, and the pale artichoke pieces will become evenly distributed. Season with salt, pepper, paprika, and cayenne if using. Taste and adjust seasoning – the dip should be savoury and well-balanced.

Add the cheese and melt. Fold in the grated mozzarella and half of the grated Parmesan. Stir until the mozzarella has completely melted into the sauce, creating long, elastic strands. The dip will become thick, glossy, and incredibly fragrant. Remove the pan from the heat.

Bake to golden perfection. Preheat your oven to 200°C (180°C fan/gas 6). Transfer the mixture to a small ovenproof baking dish (about 20cm round or square). Smooth the top with a spatula. Sprinkle the remaining Parmesan cheese evenly over the surface. Bake for 15-20 minutes, or until the dip is bubbling vigorously around the edges and the top is a deep, golden brown with darker spots. The cheese will have formed a crisp, irresistible crust.

Rest and garnish. Remove the dish from the oven and let it rest for 5 minutes. This allows the dip to set slightly, making it easier to scoop without it being a runny mess. Just before serving, sprinkle over the fresh chives or parsley for a pop of colour and freshness.