Key Lime Poke Cake
I created my own key lime poke cake recipe after I searched high and low and couldn't find anything I liked. It's a tart, moist, light, and amazingly delicious key lime cake.
yellow cake mix (such as Duncan Hines)
1
(15.25 ounce) package
water
1
cup
vegetable oil
⅓
cup
eggs
3
lime-flavored gelatin mix (such as Jell-O)
1
(3 ounce) package
boiling water
1
cup
key lime juice, or more to taste
¼
cup
eggs
2
egg yolks
2
white sugar
1
cup
lime juice, or more to taste
¾
cup
lime zest, or to taste
4
teaspoons
cornstarch
½
teaspoon
butter
¼
cup
green food coloring (Optional)
2
drops
whipped topping (such as Cool Whip)
1
(8 ounce) container
 Preheat the oven to 350 degrees F (175 degrees C). Grease a 9x13-inch baking pan.
  Make the cake: Beat cake mix, water, oil, and eggs in a large bowl with an electric mixer on low speed until moistened. Increase the speed to medium and beat for 2 minutes. Pour batter into the prepared baking pan.
  Bake in the preheated oven until a toothpick inserted into the center comes out clean, 24 to 29 minutes.
  Make the poke filling: Dissolve gelatin mix in boiling water. Add key lime juice and mix well.
  Use a fork to poke holes all over the cake. Spoon poke filling all over cake, then place into the refrigerator to cool while you make the curd and frosting.
  Make the lime curd: Whisk eggs and egg yolks together in a large glass bowl. Combine sugar, lime juice, lime zest, and cornstarch in a smaller heatproof bowl.
  Place the heatproof bowl with the sugar mixture over a pot of simmering water. Stir frequently, scraping down the sides with a rubber spatula to avoid scorching, until boiling, about 5 minutes.
  Slowly whisk the hot sugar mixture, little by little, into beaten eggs. Place the bowl over the pot of simmering water and whisk until the curd coats the back of a spoon, up to 10 minutes. Remove from the heat; mix in butter until melted.
  Drop food coloring into the curd and mix to achieve your desired shade. Let cool to room temperature, at least 30 minutes. Cover surface directly with plastic wrap and refrigerate until completely cool, about 2 hours.
  Make the frosting: Transfer 3/4 of the curd to a separate bowl. Add whipped topping and fold together until well combined. Spread frosting over the cake. Refrigerate until set, at least 2 hours more.
  Top the poke cake with the remaining lime curd.
