Melt the butter in a large heavy-bottomed pot or Dutch oven over medium-high heat.

Add the beef cubes and sear them until they are deeply browned on all sides, then remove the beef and set aside.

In the same pot, add the chopped onion and sauté until softened and starting to turn golden brown.

Sprinkle the flour over the onions and stir constantly for 2-3 minutes until the flour turns a nutty light brown color.

Slowly pour in the beef broth while stirring vigorously to scrape up any browned bits (fond) from the bottom of the pot.

Return the beef to the pot, cover, and reduce heat to low; simmer gently for 45 minutes.

Add the cubed potatoes, carrots, rutabaga, salt, and pepper to the pot.

Cover and continue to simmer for another 35-45 minutes, or until the vegetables are tender and the sauce has thickened.

Mash a few of the potato chunks against the side of the pot to thicken the stew further if desired.

Taste and adjust salt and pepper, then serve hot garnished with fresh parsley.