Preheat your oven to 400°F, placing the top rack in the centre.
For the crust, combine flour, salt, and shortening in a bowl, mixing until crumbly.
Gradually add ice-cold water, forming a dough.
Roll out the dough and fit it into a pie plate, trimming as needed, then crimp the edges.
Blind bake the crust for 15 minutes before pouring in your filling.
For the filling, combine the milk, cream, eggs, sugar, salt, cornstarch, and gelatin over medium-low heat and whisk until thickened. Stir in butter and vanilla.
Layer sliced bananas in the crust before pouring the custard over.
Bake at 350°F for 20-25 minutes, then cool and chill before serving.