In a mixing bowl, combine the softened butter, white miso paste, and minced garlic. Mix until well combined and smooth. Set aside.

In a skillet over medium heat, add olive oil. Once hot, add the sliced shallots. Cook, stirring occasionally, until the shallots are deeply caramelized and slightly burnt, about 10-15 minutes. Remove from heat and let cool slightly.

Pat the top sirloin steak dry with paper towels. Season generously with salt and pepper on both sides.

Once the burnt shallots have cooled slightly, mix them with the dried oregano. Press this mixture onto the surface of the steak, ensuring an even coating.

Preheat a grill or skillet over high heat. Once hot, add the steak and sear for about 4-5 minutes on each side for medium-rare, or cook to your desired doneness. Use a meat thermometer for accuracy (130°F for medium-rare).

Remove the steak from the heat and let it rest for 5-10 minutes. This allows the juices to redistribute.

Slice the steak against the grain. Top each serving with a dollop of the miso-garlic compound butter and garnish with fresh parsley.