Meyer lemons seem to be available in my area during late winter and this pie always seems to prepare me for the Spring. I saw this lattice decoration on a tart when I was visiting France and always thought it was clever and beautiful. —Lisa Keys
For the crust, combine the flour, sugar and salt in a mixing bowl; cut in shortening and butter.
Add water and mix until just combined. Shape into a disc, wrap in plastic and chill 15 minutes.
Roll out dough on a lightly floured surface and fit into a 9 to 10-inch tart pan with removable bottom.
Line the tart shell with aluminum foil and weigh down with dry beans or pie weights. Place tart shell on a baking sheet. Bake at 375F for 20 minutes. Remove foil and weights and bake 10 minutes more or until a light golden brown. Reduce oven temperature to 325F.
Meanwhile, prepare filling. In a medium saucepan, whisk eggs, egg yolks, sugar, lemon juice and zest. Add butter and stir over medium heat for 5 minutes or until mixture thickens and reaches 170F. on an instant read thermometer.
Remove from heat; stir in heavy cream. Pour filling into warm pie shell.
For lattice topping, beat egg whites and cream of tartar to soft peaks. Gradually add sugar and vanilla beating to stiff peaks.
Pipe meringue over tart in a lattice pattern. Bake 20 minutes or until meringue is golden brown. Cool and chill pie before serving.