Authentic key lime pie is a recipe straight from the Florida Keys! The key lime base is topped with delicious meringue and uses easy to find ingredients!
Bake the crust. Place the pie crust in the pie dish and pinch the edges of the pie to the grooves in the pie dish. Pierce the pie dough with a fork a dozen times, then place the pie weights in the bottom of the dish. If you do not have pie weights, use dried rice or dried beans. Bake the pie according to package instructions. Halfway through the cooking time, remove the pie weights.
Make the key lime filling. Preheat the oven to 325 degrees. Crack the eggs and separate the yolk from the whites. Separate them into two different bowls. Combine the sweetened condensed milk and egg yolks. Add the key lime juice (and food coloring if desired), start with 1/3 cup, but increase to 1/2 cup if you like it on the more tart side. Pour the pie filling into the pie crust, then bake for 10 minutes. Remove the pie from the oven and let it cool for 5 minutes.
Make the meringue. While the pie is cooling, whip up the meringue. Add the egg whites to a stand mixer with a whisk attachment on high speed. Whisk until the egg whites creat peaks, about 5-10 minutes. Slowly add the sugar and the cream of tartar to the egg whites, then whisk for another 2-3 minutes.
Assemble the pie. Use a rubber spatula to spoon the meringue over the key lime pie. Seal the edges of the pie crust with the meringue by sliding your spatula along the edges with more meringue.
Bake then cool. Preheat the oven to 350 degrees. Place the meringue topped pie into the oven on the middle rack. Increase the oven by 25 degrees every two minutes. Turn the oven light on and watch the meringue so you don't burn it. Do not walk away from the pie, it browns quickly! Remove the pie from the oven and allow it to cool on the counter for 1 hour, then place in the fridge for 3-4 hours. Warm a knife under hot water before slicing the pie. Mangia!