Walnut Crumble Pumpkin Pie

We all have a sweet tooth here in this house, but I always refrained from making nice tarts and cakes, because it was just too much cake for two people if I made a regular one in a normal-sized tart pan.
Last week I bought a 5 inch tart spring form, determined to start baking nice cakes for my husband and me or the occasional visitor. The amounts in the recipe given below are for a regular 9 inch tart pin though.
My 5 inch spring form debuted with this delicious pumpkin pie, made with home-cooked pumpkins and coconut milk, and based and topped up with a walnut cinnamon crumble. Do I need to say that the cake was gone the same day?

(Print Recipe)

Pie Crust
1 1/4 cups whole wheat flour
1/2 teaspoon salt
1/2 tablespoon palm sugar
1/2 cup butter, chilled
1/4 cup ice water (or less)

Pie Filling
1/2 cup palm sugar
1 teaspoon salt
1 teaspoon ground cinnamon
1/2 teaspoon ground ginger
1/2 teaspoon ground nutmeg
1 1/2 cups of pumpkin puree
1 teaspoon vanilla extract
2 eggs
1 cup coconut milk

Walnut Crumble Topping
1/2 teaspoon ground cinnamon
1/4 cup packed palm sugar
2 tablespoons whole wheat flour
2 tablespoons butter
3/4 cup chopped walnuts

Make one 9-inch cake
Pie Crust
In a food processor, place the flour, salt, and sugar and process until combined. Add the butter and process until the mixture resembles coarse meal. Pour half of the water in a slow, steady stream, through the feed tube until the dough just holds together when pinched. Add remaining water, if necessary.
Turn the dough out onto your work surface. Flatten the dough into a disk, cover with plastic wrap, and refrigerate for 30 minutes to one hour before using. This will chill the butter and allow the gluten in the flour to relax. At this point you can also freeze the dough for later use.
On a lightly floured surface, roll out the pastry to fit into a 8 or 9 inch tart pan. To prevent the pastry from sticking to the counter and to ensure uniform thickness, keep lifting up and turning the pastry a quarter turn as you roll (always roll from the center of the pastry outwards to get uniform thickness). To make sure it is the right size, take your tart pan, flip it over, and place it on the rolled out pastry. The pastry should be about an inch larger than your pan.

Pumpkin Pie Filling
In a mixing bowl, combine the pumpkin, coconut milk, eggs, cinnamon, ginger, nutmeg and salt.

Walnut Crumble Topping
In a small bowl, combine sugar, flour, and 1/2 teaspoon cinnamon. Cut in the butter until the mixture is crumbly. Stir in walnuts.

Baking the Pie
Preheat the oven to 200C.
Oil an 9-inch tart spring form. Gently lay the rolled out pastry dough in the pan, lightly press pastry into bottom and up sides of pan. Prick bottom of dough with a fork (this will prevent the dough from puffing up as it bakes). Place rack in center of oven and bake for about 10 minutes. Take out the form. Sprinkle half of the walnut mixture evenly over the pie crust. Then pour pumpkin batter into the pie crust.
Turn down oven heat to 170C. Put the pan back int he oven and bake for another 20 minutes. When the batter has set a little, take out the pan again and sprinkle the other half of walnut mixture evenly over the pie. Put back in the oven and bake for another 30 minutes. Let cool. Serve with whipped cream or creme fraiche.