Sift together the flour, salt, and baking powder. Mix in the poppy seeds. Cut the butter into small chunks and add it to the flour mixture. Cut the butter into the flour mixture until it is the size of peas.
Stir the orange zest into the cream. Pour the cream into the flour mixture all at once and stir rapidly with your hand to form a soft dough. Take care not to overmix.
Place on a floured work surface and pat out to a rectangle 1½ inches (3.7 cm) thick. Make 1 rough single turn (see Figures 5-6 and 5-7), shaping the dough with your hands and not a rolling pin. The biscuit dough can be covered and refrigerated for 1 day at this point, if desired.