To begin, preheat your oven to 175°C (160°C fan). In a large pot, place the cubed rutabaga, add 1 tsp of salt, and cover with water. Bring to a boil, then reduce to a simmer. Cook for 30–40 minutes, or until fork-tender.

Once the rutabaga is tender, drain thoroughly and return to the pot. Mash until completely smooth. For best results, use a potato ricer or stick blender to achieve a velvety texture.

In a small bowl, beat the egg lightly. Stir the egg, cream, dark syrup, flour, nutmeg, white pepper, remaining salt, and melted butter into the mash. Mix until fully combined and evenly seasoned.

Taste the mixture and adjust seasoning if needed. Traditional Lanttulaatikko should strike a delicate balance between sweet and earthy. If your rutabagas are particularly bitter, a touch more syrup can soften the edge.

Grease a medium baking dish (about 1.5L capacity) with butter. Sprinkle the bottom with a dusting of breadcrumbs for added texture and a subtle crunch.

Pour the rutabaga mixture into the prepared dish. Level the top with a spatula, then create a decorative pattern using the back of a fork, a traditional touch that also enhances browning.

Sprinkle a light layer of breadcrumbs over the top. Dot with small bits of butter to encourage a golden crust during baking.

Place the dish on the middle rack and bake uncovered for 1 hour, or until the surface is browned and set. The edges should begin to pull slightly from the sides of the dish.

Once baked, let the casserole rest for 10–15 minutes before serving. This allows the flavours to settle and the texture to firm. Serve warm as a side to roast pork, ham, or turkey, or alongside other Finnish casseroles like porkkanalaatikko.

To serve, garnish with a pat of butter or a sprinkle of chopped fresh parsley if desired. While traditionally part of a Christmas spread, Lanttulaatikko can elevate any roast dinner. Its mellow sweetness and silky consistency pair beautifully with savoury mains and sharp lingonberry jam.