Preheat the oven to 350°F. Lightly grease a 9-inch pie pan. In a mixing bowl, stir together all ingredients. Firmly press the mixture on the bottom and up the sides of the pan. Bake for 10-12 minutes or until lightly browned. Transfer to a wire rack and let cool completely before filling, about 1 hour.

Place eggs in a medium saucepan and whisk until combined. Whisk in the sugar, salt, lime juice, tequila (if using), and zest. Add the diced butter to the pan and turn on the heat to medium. Constantly whisk until the butter melts and the mixture begins to thicken, 5-10 minutes. (Pay close attention and continue whisking to make sure it doesn't boil.) Once thick, remove from the heat and pour into the prepared crust. Let cool and set completely at room temperature, at least 1 hour. Refrigerate uncovered until ready to serve.

In the bowl of an electric mixer, add all ingredients. Beat until the cream stiffens, about 5-6 minutes. Serve on top of pie slices with some additional lime zest, if desired.