1 large lime, scrubbed (for 1 teaspoon zest and 2 tablespoons juice)
4 large eggs
1 (18.25 ounce) box plain yellow cake mix
1 (3 ounce) box vanilla instant pudding mix
1 1/4 cups water
1/3 cup vegetable oil
1 teaspoon coconut flavoring
1 (14 ounce) can sweetened condensed milk
1/3 cup Key lime juice
1/4 teaspoon cream of tartar
Reserved 3 large egg whites
1/2 teaspoon coconut flavoring
1/3 cup granulated sugar
Place a rack in the center of the oven and preheat the oven to 350 degrees F.
Line 24 cupcake cups with paper liners. Set pans aside.
Prepare the cupcake batter: With a citrus zester or fine grater, zest the lime
and reserve 1 teaspoon.
Cut the lime in half and squeeze the juice over a strainer
into a small bowl; you should have 2 tablespoons. Set aside.
Separate 3 of the eggs. Place the whites in a large clean mixing bowl and the
yolks in another mixing bowl.
Add the remaining egg, cake mix, pudding mix, water, oil, coconut flavoring and
lime zest and juice to the yolks. Blend with an electric mixer on low speed for
30 seconds. Stop the machine and scrape down the sides of the bowl with a rubber
spatula. Increase the mixer speed to medium and beat for 2 minutes more, scraping down
the sides again if needed. The batter should look well blended.
Spoon or scoop 1/4
cup batter into each lined cupcake cup, filling it two thirds of the way full. Place
the pans in the oven.
Bake the cupcakes until they are lightly golden and spring back when lightly
pressed with your finger, 18-22 minutes. Remove the pans from the oven and place
them on wire racks to cool for 5 minutes. Increase the oven temperature to 450 degrees
Run a dinner knife around the edges of the cupcake liners, lift the cupcakes
up from the bottoms of the cups using the end of the knife, and pick them out of
the cups carefully with your fingertips.
Place them on a wire rack to cool for 15
minutes before filling.
Meanwhile, prepare the filling.
Place the sweetened condensed milk and Key lime juice in a small bowl and stir
to combine. Spoon the mixture into a pastry bag fitted with a medium tip. Press
the tip 1/4 inch into the top center of each cooked cupcake and squeeze the bag
to release about 1 tablespoon filling into the cupcake. Scrape off any excess filling
with a rubber spatula.
Place the cooled cupcakes nearly side by side on a baking
Prepare the meringue: Add the cream of tartar to the reserved egg whites and
beat with an electric mixer on high speed until frothy, 45 seconds.
Add the coconut
flavoring and 1 tablespoon of the sugar. Continue beating on high, adding 1 tablespoon
sugar at a time, until the whites form stiff peaks (if you pull the beaters from
the meringue, the meringue should extend from the beaters in straight stiff peaks).
Spoon 2 tablespoons meringue onto the top of each cupcake and swirl to spread it
just to the edges with a short metal spatula or a spoon.
Place the pan in the oven.
Bake until the meringue is light nutty brown in color, 5 to 6 minutes.
Run a dinner
knife around the edges of the cupcake liners, lift the cupcakes up from the bottoms
of the cups using the end of the knife, and pick them out of the cups carefully
with your fingers.
Serve at once, or allow the cupcakes to cool 10 minutes, then serve.
Store in a cake saver at room temperature, for up to 3 days.