Begin by making the pie dough. Place the flour, sugar and salt into the bowl of a food processor fitted with a chopping blade and pulse to combine. Add the butter and pulse until the butter chopped into the flour about the size of peas. Slowly add the ice cold water, pulsing as you go, until the mixture starts to clump together. Remove from the food processor and divide the dough into two pieces. Flatten each into a disc and wrap in plastic wrap and refrigerate for 30 minutes to an hour.
Remove one portion of the dough and place on a piece of baking paper lightly dusted with flour. Lightly dust the top with flour and place another piece of baking paper on top and roll out the dough until roughly 3mm (1/8 inch) thick. Take 4 individual pie dishes and lightly grease with butter and line with the dough, leaving some overhang. Refrigerate. Remove the second portion of dough and roll out to the same thickness as the first portion and place on a baking tray and refrigerate for 30 minutes.
Preheat the oven to 200 celsius (400 Fahrenheit). Meanwhile make the pie filling. Chop the apple and rhubarb into bite size pieces and place in a bowl with the lemon zest, spices, sugar and salt. Set aside.
Remove the lined pie tins and sprinkle almond meal in the bottom and divide the apple and rhubarb mixture, along with the juices, between the bases along with the butter.
Take the second portion of dough out of the refrigerator and cut into strips approximately 10mm (1/2 inch) thick.
Take 5 strips of the dough a place parallel across the top of the pie, leaving a little gap in between each strip. Fold back every other strip of dough at the top of the pie and place one long strip of dough across the parallel strips, just after the folds. Unfold the fold strips and place over the strip of dough you just added. Now fold back the alternate strips of dough (the strips that weren't folded over previously) and place another strip of dough across the parallel strips. Repeat until the top of each pie is covered. Take a fork and press down the edge of the pie, trimming off any excess.
Place the pies on a baking tray and lightly brush with milk and sprinkle with sugar and bake for 30 minutes, or until lightly golden and the juices bubble up to the top of the crust. Serve with a dollop of cream or ice cream, or both!
If the top of your pie browns too quickly cover with foil.