Step 1 Heat the oven to 375 degrees.
Step 2 Stir the almonds into the mincemeat; set aside.
Step 3Combine the flour and salt in a bowl. Cut in the butter until evenly blended with the flour. Drizzle the ice water over top and use a fork to mix the dough until a ball forms. Divide the dough into 3 parts.
Step 4Roll one portion of dough out on a lightly floured surface. Using a 3 1/4-inch round cutter, cut out 12 rounds of dough. Press the rounds of dough into the bottom and sides of a 12-cup mini-muffin pan. Fill each cup with 1 tablespoon of mincemeat. Fold the edges of the dough over the filling (the centers will be open). Brush the edges of the crust with the beaten egg.
Step 5Bake until the dough is lightly browned, about 20 minutes. Remove from the oven; let the mini-tarts cool in the pan a few minutes until they're easy to handle, then remove to a wire rack to cool. Repeat with each of the remaining two portions of dough and filling.