Preheat oven to 350 °F and coat two small loaf pans with non-stick baking spray.
In a large mixing bowl, combine the cake mix, water, melted butter, egg, key lime juice, key lime zest and gel food coloring (if using).
Divide the batter between the two pans. Gently tap the pans on the countertop to help release any air bubbles in the batter.
Place the loaf pans onto a large baking sheet and into the oven to bake for 30-35 minutes, or until a toothpick inserted in the middle of the cake comes out clean.
Remove from oven and place on a wire rack to cool for 10 minutes before flipping the bread out of the pans.
To Make the Glaze
Place the cooled pound cake loaves on a wire rack, with a baking sheet underneath to catch any drips.
In a medium bowl, whisk together the powdered sugar, lime juice and lime zest until combined and smooth.
Slowly pour the glaze over the two cakes.
Allow to set before cutting and serving.
Notes
Nutrition information is provided as an estimate only.Prep Tips:
Yield - Makes 2 small mini loafs.
Pan Size - We used two half loaf pans for this recipe. Either 6 in x 3.5 in or 5.75 in x 3 in size would work. If you want to bake this in one large loaf pan, you'll likely need to increase the baking time slightly. Use a toothpick to check for doneness.
Storage - Keep in an airtight container at room temperature for 3-4 days. This cake can also be frozen in a freezer bag or container, for up to 2 months.