To begin, preheat your oven to 150°C (fan 130°C). Take a large, ovenproof baking dish or casserole and lightly grease it with butter. This prevents sticking and helps develop a lovely crust during baking.

In a medium bowl, combine the pearl barley or rice with water. Let it soak for 10 minutes. This softens the grains and helps them absorb liquid evenly, producing a smoother porridge.

Drain the soaked grains and add them to the prepared baking dish. Pour in the milk and stir in the salt. Mix gently to distribute the grains evenly throughout the dish.

Add a tablespoon of butter in small dots over the surface. This enriches the flavour and encourages a golden, baked finish on top.

Carefully place the baking dish, uncovered, on the middle oven rack. Bake for 2 hours, stirring once halfway through to prevent the grains from settling at the bottom.

Check the porridge after 90 minutes. The texture should be thick, with the top just beginning to brown. If it seems too dry, add a splash of warm milk and gently stir.

If you prefer a caramelised crust, increase the oven temperature to 180°C for the final 15 minutes. Watch closely to prevent overbaking.

Once done, remove from the oven and let it rest uncovered for 10 minutes. This helps the porridge firm up slightly and enhances its creamy consistency.

To serve, spoon the porridge into bowls. Top with a small pat of butter, a sprinkle of sugar, cinnamon or a generous spoonful of lingonberry jam. For extra richness, add a splash of cold milk around the edges.

Uunipuuro is traditionally enjoyed warm and unadorned, but feel free to add your favourite toppings. It pairs beautifully with tart berries and even a spoon of thick yoghurt. Serve directly from the baking dish for a rustic presentation.