1. Make crust: Preheat oven to 350 degrees. Lightly butter six standard muffin cups. In a food processor, process butter, flour, sugar, and salt until mixture resembles coarse meal. Add yolks and vanilla and process until dough comes together when pressed (dough will be crumbly).

2. Divide dough into 6 pieces. Roll each into a ball and place in a muffin cup, pressing evenly into bottom and up sides. Place a paper cupcake liner into each muffin cup over dough and fill with pie weights or dried beans. Bake until edges are dry, 15 minutes. Carefully remove liners and weights; bake until crusts are dry and barely golden, 5 to 7 minutes.

3. Meanwhile, make filling: In a medium bowl, whisk together eggs, flour, sugar, lime juice, and salt. Place 3 cherry halves into each crust and divide filling among each. Bake until filling is set, about 25 minutes. With the tip of a knife or a small offset spatula, remove cups from pan. Let cool completely on a wire rack.