This reminds me of a margarita in pie form. Maddy made an emergency key lime run for the last 1/4 cup of the juice. Try to get fresh key limes if you can, otherwise, there are some good bottled key lime juices. You will notice the pie is NOT green. If you have green key lime pie you can be sure they added food coloring.
1.5 cups finely ground pretzels--I used the thin rods--better salt to pretzel ratio
1/4 cup sugar
1 stick butter, melted
Grind the pretzels with the sugar in a food processor. Add melted butter and press into a 9" pie pan. Bake at 350 degrees for 8-10 minutes. The crust won't change color. Prepare filling while shell cools.
4 egg yolks
2 14 oz. cans sweetened condensed milk
3/4 cup key lime juice
whisk egg yolks and sweetened condensed milk until well combined. Add lime juice and stir til smooth. Pour into pie crust. Bake at 350 for ~30 minutes until set. Chill at least two hours in refrigerator.