1. Preheat the oven to 350°F. Prep the crust: In a medium bowl, combine the crushed graham crackers, brown sugar, salt, and melted butter. Mix until a wet, sand-like texture is formed. Then empty the mixture into a 9-inch pie plate. Use the bottom of a flat glass (or measuring cup) to evenly press the crumbs onto the bottom and up the sides of the pie plate.
2. Bake the crust for 10 minutes. After baking the crust, set it aside to cool while you make the filling- do not shut off the oven.
3. In a medium bowl, whisk the egg yolks together. Then stir in the sweetened condensed milk and lemon zest. Whisk in the lemon juice, salt, and vanilla bean paste/extract until everything is thoroughly combined. Carefully pour the lemon filling onto the cooled pie crust. 
4. Bake the lemon pie for 17-20 minutes, or until the filling is mostly set but gives the slightest jiggle/wobble.
5. Place the pie onto a wire rack to cool down completely. Then carefully place a sheet of foil over the pie and refrigerate for at least 4 hours, or preferably overnight for the best results.

For the meringue topping:

1. Fill a small saucepan with a few inches of water and bring to a simmer over medium heat. Using a small, heatproof bowl, place the egg whites, sugar, cream of tartar, and salt into the bowl. Place the bowl over the saucepan, creating a double boiler- make sure the water in the saucepan is not touching the bottom of the bowl.
2. Continuously whisk the mixture together until the sugar dissolves and the mixture goes from thick to thin, about 5-6 minutes. As you continue to stir, look for the mixture to get somewhat frothy and warm. Carefully, test the mixture by dipping a finger in, you should feel no sugar granules when rubbing between your fingers. To be precise, use a thermometer to check for a temperature of the mixture to reach 160°F.
3. Turn off the heat and remove the small bowl from the top. Stir in the vanilla bean paste/vanilla extract, whisk to fully combine.
4. Beat the mixture: Add the meringue into the bowl of a stand mixture (with whisk attachment) or use a handheld mixer; beat the meringue on high speed until fluffy with stiff peaks, about 5-7 minutes. Lift the beater and look for the meringue to stand tall without weeping. 
5. Evenly spread the meringue onto the chilled lemon pie. Serve as is or use a kitchen torch to lightly toast the meringue, as pictured. Slice the lemon meringue pie into wedges and serve immediately. Enjoy!