01 - Combine sirloin cubes with olive oil, salt, black pepper, and smoked paprika in a mixing bowl. Mix thoroughly and allow to marinate while preparing potatoes.
02 - Heat olive oil in a large skillet over medium-high heat. Add quartered baby potatoes, season with salt and black pepper, and sauté, stirring occasionally, until golden brown and fork-tender, approximately 12 to 15 minutes. Transfer potatoes to a plate and keep warm.
03 - Increase skillet heat to high. Arrange marinated steak cubes in a single layer, working in batches if necessary. Sear undisturbed for 2 minutes, then turn and cook for an additional 2 to 3 minutes until browned to your preferred doneness. Remove steak bites and set aside.
04 - Lower heat to medium and add unsalted butter to the skillet. Once melted, add minced garlic and dried thyme. Sauté for 30 seconds until fragrant.
05 - Return potatoes and steak bites to the skillet. Toss thoroughly in the garlic butter until evenly coated and heated through, about 1 to 2 minutes.
06 - Sprinkle with chopped fresh parsley and serve immediately.