Cinnamon Tart
The Cookbook of Sabina Welserin, Translation (c) Valoise Armstrong 1998.
Nim ain halb pfúnd mandel, mer oder minder, gestosen, darnach man sý will grosß machen, nim púterschmaltz, siben air, das weisß darúon, solchs dúrchainandergemischt, nachmals ain lot rerlen darúnder, doch der merer tail daraúfgestret vnnd die torten mit rossenwasser besprengt, aúch soll man darzú nemen vngeferlich ain 1/2 pfúnd zúcker, daranthon/jst aúch gút/ nemlich ain eitterlin vom kalb gesotten vnnd klaingehackt.

Take a half pound of ground almonds, more or less, according to how large a tart one will make. Take butter and the whites from seven eggs. Mix everything together, afterwards put a half ounce of cinnamon into it, the largest part, however, sprinkled on top, and sprinkle the tart with rose water. Also take about a half pound of sugar and put it in. The white fat from a leg of veal, cooked and finely chopped, is also especially good.

2 C
Ground Almonds
1 C
Sugar
7
Egg Whites
1/2 C
Butter (1 stick)
1/2 oz
Cinnamon (must be Cannel and not the more readily available Cassia)
1
Pie Shell
Mix Almonds and sugar; soften butter and work in well (like a pastry). Add egg whites & mix well. Add all but a scant tablespoon Cinnamon and mix well. Pour mixture into pie shell. Mix a scant tablespoon sugar with reserved cinnamon and sprinkle over pie. Bake at 350F for 1 hour.
If you are having difficulty finding the period Cannel cinnamon check in markets that cater to Hispanic cooking. If you cannot find the period cinnamon I would not recommend making this tart, modern cinnamon has a coarser texture and flavor that would not be pleasing.