Named after the old Hotel Rydberg in Gamla Stan (1857-1914), Stockholm, Biff Rydberg is simply three main ingredients, good quality beef, potatoes and onions. Still, it is surprisingly difficult to do well. The result depends on proportion, time, and temperature and this is why the dish is one of the more expensive ones on restaurant menus in Stockholm.

The beef, potatoes and onions are diced and fried at different temperatures and served with a mustard cream.

But what I like the most about this recipe, is the idea of simple ingredients raised to be extraordinary. If translated to architecture, it relates to the vernacular and simple and ordinary materials put together with care.

Serves: 4    Total time: 40 min

INGREDIENTS

400 – 500 g fillet of beef
2 yellow onions
4 large potatoes
Butter and oil for frying
Salt and pepper to taste

MUSTARD SAUCE

200 ml whipping cream
1 tbsp Dijon mustard
1 tbsp mustard powder
1 egg yolk
1 tbsp caster sugar
Pinch of salt
Pinch of black pepper

METHOD

Peel the potatoes and onions and cut into cubes, including the beef. Rinse the potatoes in cold water to remove the starch. It is important that all the pieces are the same size to avoid some pieces being undercooked or burned.

Over a medium heat, slowly fry the onions in butter or oil until soft, transparent, and lightly caramelised (20 min).

Over a medium-high heat, fry the potatoes in butter until soft inside and golden and crisp on the outside (25 min). Use a large skillet or pan to avoid overcrowding and steamed or soggy potatoes.

Season the beef with salt and pepper, and over a high heat, sauté in oil until brown on the outside and pink and juicy on the inside (a few minutes only). Avoid overcrowding the pan.

Whip the cream lightly. Add the egg yolk, mustard, sugar, salt and pepper.

Serve the beef, potatoes and onion alongside each other and spoon over the mustard sauce.

This is a photograph from a construction site visit in Lille. The terracotta blocks are an economic and local way of building a partition wall in France. Before applying the final finish, the blocks are jointed with mortar creating a beautiful pattern.