Season the Steak: In a bowl, toss the steak cubes with Cajun seasoning, salt, and black pepper until evenly coated.

Heat the Oil: In a large skillet, heat the olive oil over medium-high heat.

Cook the Steak Bites: Add the seasoned steak cubes to the skillet in a single layer. Cook for about 2-3 minutes without stirring to get a nice sear. Then, flip the steak bites and cook for an additional 2-3 minutes, or until they reach your desired level of doneness (medium-rare is typically 130-135°F or 54-57°C). Remove the steak bites from the skillet and set aside.

Make the Garlic Butter Sauce: In the same skillet, reduce the heat to medium and add the butter. Once melted, stir in the minced garlic and cook for about 1 minute until fragrant, being careful not to burn it.

Combine and Serve: Return the cooked steak bites to the skillet and toss them in the garlic butter sauce until well coated. Cook for an additional minute to heat through.

Garnish: Remove from heat, garnish with chopped parsley, and serve immediately. Optionally, squeeze fresh lemon juice over the steak bites for added brightness.