Prep and pat dry. Cut the steak into 1-inch cubes. Pat very dry with paper towels. Dry steak browns better, so don’t skip this step. Season all over with 1 teaspoon kosher salt and 1/2 teaspoon black pepper.

Slice the zucchini. Halve lengthwise, then cut into half-moons about 1/2 inch thick. Lightly season with a pinch of salt. Set aside.

Heat the pan. Place a large skillet (cast iron is ideal) over medium-high heat. Add 1 tablespoon olive oil. When it shimmers and a drop of water sizzles, the pan is ready.

Sear the steak in batches. Add half the steak in a single layer. Don’t crowd the pan. Sear 2 to 3 minutes without moving, then flip and cook 1 to 2 minutes more for medium-rare to medium. Transfer to a plate. Repeat with remaining steak, adding more oil if needed. Keep the browned bits in the pan.

Cook the zucchini. Reduce heat to medium. Add 1 tablespoon butter. Add the zucchini in a single layer. Let it cook undisturbed 2 minutes to get color, then toss and cook 2 to 3 minutes more until just tender with some golden edges.

Make the garlic butter. Push zucchini to the edges. Add 2 tablespoons butter to the center. When melted, stir in the minced garlic. Cook 30 to 45 seconds until fragrant. Don’t brown the garlic.

Combine and glaze. Return steak and any juices to the skillet. Toss everything in the garlic butter. Add lemon zest and a squeeze of lemon juice (start with 1 to 2 teaspoons). Taste and adjust salt and pepper. For extra savoriness, add a few drops of Worcestershire or soy sauce.

Finish and serve. Turn off heat. Fold in chopped fresh herbs. Sprinkle with red pepper flakes or Parmesan if you like. Serve hot with your favorite sides or over rice, cauliflower rice, or mashed potatoes.