Beat butter, cream cheese, sugar, salt and almond extract until light and fluffy, 3 minutes. Stir in flour until smooth. Stir in almonds. Shape dough into 10-inch log. Wrap in plastic wrap; refrigerate at least 2 hours or overnight.
Heat oven to 350°F. Slice dough into 30 equal pieces. Press each in bottom and up side of ungreased 1-3/4 x 1-inch gem muffin-pan cup to form a shell, for a total of 30.
Bake at 350°F for 15 to 20 minutes, until lightly browned. Transfer pans to racks; cool slightly. Lift shells out and set on racks to cool completely.
Melt white chocolate and shortening. Let cool slightly. Spoon 1/4 teaspoon into bottom of each shell; let stand 10 minutes. Spoon about 3/4 teaspoon mint jelly into each. Drizzle tops with remaining chocolate.
