9-in prepared Graham Cracker Pie Crust (or larger)
2 cans Sweetened Condensed Milk
4 Egg Yolks
1/2-3/4 c. Key Lime Juice (must use real key lime juice, not regular)
Few drops of green food coloring (optional)
Cool Whip topping
Preheat oven to 350. Mix milk, yolks, and juice in bowl, then taste to ensure it is tangy. Mix in 2-3 drops of food coloring. Pour filling in shell and cook for 15 minutes, just to set. Cool for 15 minutes. Refrigerate until fully cooled. Top with Cool Whip and serve.