Mix the oats, almonds, brown sugar, cinnamon, and salt together in a large mixing bowl until combined. In a small, separate bowl, stir the melted butter, honey, vanilla and egg white together, then drizzle over the oat mixture, stirring together until well-combined.
4 cups old-fashioned rolled oats, 1 1/2 cups sliced almonds, 1/2 cup light brown sugar, 1/2 teaspoon cinnamon, 3/4 teaspoon kosher salt, 1/4 cup salted butter, 1/3 cup honey, 2 teaspoons vanilla, 1 egg white