This is not your typical cheesecake. These nutmeg-infused tartlets are set with rennet, an extract from the lining of calves' stomachs often used in making cheese. It is sold in tablet form, sometimes called Junket; check your supermarket's baking section.
1 sheet (about 1/2 lb.) thawed frozen puff pastry
1 rennet tablet
1 cup milk
1 tbsp. butter
1/2 cup sugar
1 beaten egg
3/4 cup angel-food cake crumbs (tear cake into small pieces)
1 tsp. ground nutmeg
3 tbsp. black currants
1. Preheat oven to 375° and butter six 4'' tart molds. Roll out 1 sheet (about 1/2 lb.) thawed frozen puff pastry on a lightly floured surface into a 12'' x 15'' rectangle. Make 6 circles, about 5'' in diameter, on pastry. Cut out circles, press into molds, and prick all over with a fork. Refrigerate while you make filling. Dissolve 1 rennet tablet in 2 tbsp. lukewarm water in a small saucepan. Add 1 cup milk, 1 tbsp. butter, and 1/2 cup sugar. Place over low heat and stir just long enough to get the sugar off the bottom of the pan, about 5 seconds. Cook, resisting the urge to stir, until mixture reaches 98°, about 10 minutes. (We recommend using a kitchen thermometer, but if you don't have one, mixture should be warm to the touch but not hot.) Remove from heat and cool for 5 minutes. Stir in 1 beaten egg, 3/4 cup angel-food cake crumbs (tear cake into small pieces), 1 tsp. ground nutmeg, and 3 tbsp. black currants. Spoon mixture (don't worry if it looks broken) into pastry shells. Bake until filling is brown and pastry golden, about 25 minutes.