Line a 9-inch round cake pan or an 8-inch square baking pan with parchment paper.

For mixed fruit: Wash cherries, and dry them. Halve or quarter as desired. In a large bowl, combine cherries, golden raisins, currants, raisins, candied peel, ground almonds, chopped almonds, lemon zest, and orange zest. Add whiskey, and let stand for 1 hour.

For almond paste: In a large bowl, whisk together ground almonds and castor sugar.

In a medium bowl, whisk together egg, whiskey, and almond extract. Add egg mixture to almond mixture, and stir until combined and a stiff paste forms. (You may not need all of the egg mixture.) Dust work surface with confectioners’ sugar; turn out almond paste, and gently knead until smooth.

Preheat oven to 350°F (180°C).

For batter: In the bowl of a stand mixer fitted with the paddle attachment, beat butter at medium speed until very soft. Add brown sugar, and beat at medium speed until light and fluffy, stopping to scrape sides of bowl. Add eggs, one at a time, beating well after each addition.

In a medium bowl, stir together flour and mixed spice. Gently stir flour mixture into butter mixture.

Add apple to mixed fruit. Add mixed fruit to batter, and gently stir just until combined. (Don’t beat mixture again or you will toughen cake.) Spoon half of batter into prepared pan. Roll about half of almond paste into an 8½-inch disk. Place on top of batter in pan, and cover with remaining batter. Make a slight hollow in center. Dip your hand in water, and pat surface of batter. (This will ensure top is smooth when cooked.) Cover with a single sheet of parchment paper.

Bake for 1 hour. Reduce oven temperature to 325°F (160°C), and bake until a wooden pick inserted in center comes out clean (see Notes), 3 to 3½ hours. Pour whiskey over hot cake, and let cool completely in pan. Let stand overnight.

Remove cake from pan. Wrap cake, with parchment, in plastic wrap and foil until ready to serve.

Preheat oven to 425°F (220°C).

Roll half of remaining almond paste into a 9-inch disk. Brush cake with egg white, and top with almond paste disk. Roll remaining almond paste into 11 balls. Score top of cake in 1½-inch squares or diamonds. Brush with egg yolk, stick almond paste balls around outer edge of top, and brush with beaten egg.

Bake until slightly golden, 15 to 20 minutes. Serve warm, or let cool completely, wrap tightly in plastic wrap, and refrigerate for several weeks.