1. Pat the steak cubes dry and season them generously with salt and pepper.

2. Heat the olive oil in a large skillet over medium-high heat. Add the steak in a single layer and sear for 1-2 minutes per side until nicely browned. Remove the steak to a plate.

3. Reduce the heat to medium and add 2 tablespoon of butter and the minced garlic to the skillet. Cook for about 1 minute, stirring constantly, until the garlic is fragrant. Return the seared steak to the skillet and toss to coat the bites in the garlic butter. Transfer the steak to the plate.

4. Add the remaining 1 tablespoon of butter, beef broth, and lemon juice to the skillet. Bring the mixture to a simmer. Add the zucchini and cook for 2-3 minutes, tossing frequently, until the zucchini is just tender.

5. Return the garlic butter steak bites to the skillet with the zucchini and toss to combine. Sprinkle with fresh chopped parsley and red pepper flakes if desired. Serve immediately.