2 1/2 teaspoons vegetable oil
1 cup white sugar
2 eggs
1 egg white
1 1/2 cups all-purpose flour
1 teaspoon baking powder
1 teaspoon baking soda
1/2 teaspoon salt
1 cup shortening
1/2 cup evaporated milk
2 1/2 cups chopped pitted limes
1 cup brown sugar for topping
Heat oven to 350 degrees F. Grease cookie sheets.
In a large bowl, whisk together the oil, sugar, eggs, egg white, flour, baking powder, baking soda and salt. Stir these into a well-oiled 9x13 inch baking dish.
Bake for 8 minutes in the preheated oven, or until set. Spoon the batter over the cookie sheets, covering completely. Add limes and orange slices. Bake for another 8 minutes and sprinkle the brown sugar over the top. Bake an additional 10 minutes in the preheated oven. Cool completely before cutting into squares. December 2016 UPDATE: I've made a few changes to the recipe, including using the orange liqueur, making the pecans lime - sweetened condensed milk. Tint remaining orange juice with brown sugar, and drizzle over cookie sheet slices. Store the cookies in an airtight container in an airtight plastic bag in the freezer.