This is Recipe no. 70 from the Sabrina Welserin cookbook. Recipe 70 is for a tart with plums, but how to make a tart pastry is detailed as follows:
Bake the dough for the tart. That is made like so: take two eggs and beat them. Afterwards stir flour therein utnil it becomes a thick dough. Pour it on the table and work it well, until it is ready. After that take somewhat more than half the dough and roll it into a flat cake as wide as ou would have your tart. ... So one makes the dough for a tart." She describes adding hte filling and then putting a top on the tart.
2 eggs, whole
3/4 cup flour
Beat the eggs slightly, and add the flour. Work it until it is a dough that will roll, adding more flour as necessary. The dough will dry out quickly, I wrapped the half to top the tart in cling wrap until I was ready for it. It will roll out quite thin, which is nice.