Pat the steak cubes dry with paper towels to remove excess moisture.
Season the steak cubes evenly with kosher salt and freshly ground black pepper.
Heat olive oil in a large skillet over medium-high heat until shimmering.
Add the steak cubes to the skillet in a single layer, working in batches if necessary to avoid overcrowding.
Sear the steak cubes for about 2-3 minutes on each side until browned and cooked to your desired doneness.
Remove the steak bites from the skillet and set aside on a plate.
Reduce the heat to medium and add the unsalted butter to the same skillet.
Once the butter has melted, add the minced garlic and sauté for about 30 seconds until fragrant, stirring constantly to prevent burning.
Return the steak bites to the skillet and toss them in the garlic butter sauce to coat evenly.
Sprinkle the chopped fresh parsley over the steak bites and stir to combine.
Remove from heat and serve immediately.