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smoked porterhouse recipe with mashed potatoes

Grilled Porterhouse Steak with Garlic Herb Butter and Smashed Potatoes

Porterhouse steaks seasoned and grilled with every-minute flips to 120°F, basted with herb-infused garlic butter, served with crispy smashed potatoes.
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Ingredients Method Notes

Ingredients
  

Porterhouse Steaks:
  • 2 porterhouse steaks about 1/2 inch thick
  • 2 teaspoons kosher salt per steak
  • 1 teaspoon black pepper per steak
  • 1 teaspoon garlic powder per steak
Garlic Herb Butter:
  • 8 oz unsalted butter
  • 6 garlic cloves smashed
  • 2 sprigs fresh rosemary
  • 2 sprigs fresh thyme
Smashed Potatoes:
  • 2 lbs petite gold potatoes
  • Salt for boiling
  • Fresh chives finely chopped

Method
 

  1. Place potatoes in salted water, bring to boil, and cook 15-20 minutes until fork-tender. Drain and spread in single layer to cool completely.
  2. Melt butter over medium heat. Add smashed garlic and cook 2-3 minutes until fragrant. Add rosemary and thyme, cook 1 minute, then remove from heat. Tie additional herbs to a skewer to create basting brush.
  3. Pat steaks dry and season each with 2 tsp salt, 1 tsp pepper, and 1 tsp garlic powder per side. Rest at room temperature 30 minutes.
  4. Heat griddle over medium heat. Place cooled potatoes and smash flat with glass bottom. Cook 5-7 minutes per side until golden and crispy, basting with garlic herb butter in final minutes. Finish with chives.
  5. Preheat grill to high heat (450-500°F). Grill steaks, flipping every minute for even cooking. At 115°F internal temp, begin basting generously with herb butter using herb brush. Continue flipping and basting until internal temp reaches 120°F, about 8-12 minutes total.
  6. Rest steaks 5 minutes. Slice by removing bone, then cutting each section against the grain. Spoon warm garlic herb butter over sliced steak and garnish with chives. Serve immediately with smashed potatoes.

Notes

Let steaks rest at room temperature 30 minutes before grilling for even cooking. Flip every minute instead of once for edge-to-edge even doneness without gray bands. Pull at exactly 120°F since temperature rises during rest to 125-130°F final. The herb basting brush adds fresh aromatics when it contacts hot steak. Petite gold potatoes must cool completely before smashing or they fall apart. Crisp on medium heat, not high, to develop crust without burning. Use smashed garlic cloves, not minced, for mellower flavor that won't burn.

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