In a dry skillet over medium heat, toast the yellow mustard seeds for about 2-3 minutes, or until they begin to pop and become fragrant. Remove from heat and let cool slightly.

Once cooled, mix the toasted mustard seeds with the lemon zest, salt, and pepper in a small bowl.

Pat the strip steaks dry with paper towels. Rub each steak with olive oil and season generously with salt and pepper.

Press the mustard seed and lemon zest mixture onto both sides of the steaks, ensuring an even coating.

Preheat a grill or cast-iron skillet over medium-high heat. Cook the steaks for about 4-5 minutes on each side for medium-rare, or until they reach your desired doneness.

Once cooked, transfer the steaks to a cutting board and let them rest for 5-10 minutes.

In a small saucepan, melt the ghee over low heat. Add the minced garlic and cook until fragrant, about 1 minute.

Toss in the rosemary sprigs and increase the heat to medium. Allow the ghee to bubble and char the rosemary for about 2-3 minutes, stirring occasionally to avoid burning.

Remove from heat and strain the ghee into a small bowl to remove the rosemary and garlic bits. Stir in the lemon juice for a bright finish.

Slice the rested steaks against the grain and serve drizzled with the charred rosemary ghee butter. Enjoy with your favorite side dishes.