Really Simple Key Lime Pie

key lime juice (or as little as 1/2 cup if you prefer less tartness - you can use regular lime juice in a pinch too!)

sweetened condensed milk (14 ounce cans)

eggs

graham cracker pie crust (9" if you want an overfilled pie like the one pictured, or 11" if you're planning to do a meringue on top)

optional garnish: whipped cream