In a food processor, pulse the flour, salt & sugar. Pulse in the butter until mixture looks like sand. Pulse in the eggs. Turn out dough on a lightly floured board and mold into a round disc. Wrap in plastic. Chill for 2 hours.
Preheat the oven to 400 degrees.
Remove dough and let rest for 10 minutes. Roll the pastry dough into a 12” disc to fit inside the pan. Using the rolling pin, gently lift & roll up the crust and press into the springform pan. Press lightly to fill in any spaces. Trim any excess from the sides. Pierce the dough all over the bottom with a fork. Line pan with parchment and add in pie weights. Chill 30 minutes.
Bake for 15 minutes. Remove the pie weights and bake another 8-10 minutes until the crust is golden brown. Let cool completely.
For the filling:
Pour heavy cream and buttermilk into a heavy saucepan. Let come to a simmer. Add zest. Remove from heat. Add in the sweetened condensed milk. Stir in the lemon juice. Pour the mixture into the cooled tart crust. Let chill at least 4 hours or overnight.
Garnish with berries sliced in half and a dusting of confectioners sugar.