Arrange a rack in the middle of the oven and heat to 350°F.

Melt 1 tablespoon of the butter. Brush the bottom and sides of a 9x13-inch baking dish or foil pan with half of the melted butter. Set the remaining melted butter aside.

Whisk the eggs in a large bowl until the whites and yolks are completely mixed and the eggs are a bit frothy. Whisk in the milk and salt until just combined.

Heat the remaining 1 tablespoon butter in a large nonstick skillet over medium-low heat until melted. Pour in the egg mixture. Using a rubber spatula, scramble the eggs, stirring occasionally and pushing the cooked parts from the edges of the pan to the center, until they are just set but not dry. Remove from the heat.

Arrange the bottom half of the slider buns in an even layer in the prepared baking dish or foil pan. Top with half of the cheese. Spread the scrambled eggs in an even layer over the cheese. Sprinkle with crumbled bacon, then top with the remaining cheese. Place the tops of the buns over the cheese to close the sliders. Brush the top of the sliders with the remaining melted butter. Sprinkle with garlic powder and flaky salt.

Bake until the cheese is melted and the rolls are lightly browned, about 15 minutes. Let cool for 5 minutes before serving. Sprinkle with parsley before serving, if desired.