In a small bowl, combine 4½ teaspoons pepper, salt, and 1 teaspoon crushed juniper berries. Rub 1 tablespoon olive oil on steak to evenly coat. Rub spice mixture over steak. Let stand for 15 minutes.
In a 12-inch cast-iron skillet, heat remaining 3 tablespoons oil over medium-high heat; cook steak until crust forms on both sides and steak is cooked to desired doneness, 8 to 10 minutes, turning often to avoid burning and to keep crisp. Remove from pan and let rest for 5 to 10 minutes. Remove pan from heat and let cool for 5 minutes.
In same cast-iron skillet, melt 2 tablespoons butter over medium heat. Add shallot and onion; cook until softened. Add remaining ½ teaspoon crushed juniper berries, remaining ½ teaspoon pepper, and gin. Stir to combine, scraping bottom of pan to release steak drippings. Add chicken broth and cook until liquid is reduced by half. Add cream and simmer until thickened. Whisk in remaining 2 tablespoons butter, stirring until butter is melted.
Thinly slice steak against the grain and drizzle gin sauce over steak. Serve immediately.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/juniper-gin-steak/