1 box white cake mix
1 1/4 cups water
1 tablespoon vegetable oil
1 can (14 oz) sweetened condensed milk
3/4 cup whipping cream
1/2 cup lime juice
1 teaspoon grated lime peel
4 drops yellow food color
1 drop green food color
1 small container whipped topping
grated lime peel for garnish
Heat oven to 350°F for shiny metal or glass pan (or 325°F for dark or nonstick pan). Spray bottom only of 13×9-inch pan with non-stick spray.
In large bowl, beat cake ingredients with electric mixer on low speed 30 seconds. Beat on medium speed 2 minutes, scraping bowl occasionally. Pour into pan.
Bake 26 to 30 minutes or until toothpick inserted in center comes out clean. Cool 5 minutes. With handle of wooden spoon (1/4 to 1/2 inch in diameter), poke holes almost to bottom of cake every 1/2 inch, wiping spoon handle occasionally to reduce sticking.
In medium bowl, stir together filling ingredients (mixture will thicken). Pour over cake; spread evenly over surface, working back and forth to fill holes. (Some filling should remain on top of cake.) Refrigerate at least 1 hour.
Spread whipped topping over cake; sprinkle with lime peel. Add other garnish (lime slices, strawberries, etc.), as desired. Store covered in refrigerator.