Preheat oven to 350°F.
In a medium bowl, combine graham cracker crumbs, brown sugar, and melted butter. Press mixture into bottom and up sides of a 9-inch pie plate.
Bake until lightly browned, about 10 minutes. Let cool completely.
In a large bowl, whisk together condensed milk, eggs, and lime juice until combined. Pour into prepared crust.
Bake until set, about 10 minutes. Let cool completely.
In a medium bowl, beat cream and confectioners’ sugar with a mixer at high speed until stiff peaks form, 2 to 3 minutes. Spread whipped cream over pie. Garnish with lime slices, if desired.