Fannie's Frosted Lemon Bars

5 from 1 vote

With help from a boxed cake mix, Fannie's Frosted Lemon Bars are a perfect easy dessert to welcome Spring!

Course Dessert

Cuisine American

Keyword Cake Mix Recipe, easy lemon dessert, lemon bars

Prep Time 15

Cook Time 30

Cooling Time 2

Total Time 2 45

Servings bars

Calories 238.7kcal

Author Blair Lonergan

Preheat oven to 350 degrees F.
Spray or grease a 10 x 15-inch baking pan with non-stick spray.
In a large bowl, use an electric mixer to combine cake mix, pie filling, and eggs. The batter will be thick, but still spreadable. It’s fine if you have some lumps in the batter.
Spread batter into prepared baking pan.
Bake for 30 minutes, or until golden brown and cooked through. Allow bars to cool on a wire rack.

Once the bars are completely cool, prepare the frosting.
Combine cream cheese, sugar, butter, and vanilla extract in a large bowl. Mix with an electric mixer to combine the ingredients, and then add 1 teaspoon of milk. Mix again until completely smooth and fluffy. If the frosting is still too thick, you can slowly add one more teaspoon of milk at a time until it reaches the desired consistency (I did not need more than 1 teaspoon of milk to get the frosting to a spreadable consistency).
Spread frosting in an even layer on top of the cool lemon bars. Slice and serve immediately, or store bars in the refrigerator.

Make sure to lightly grease your baking pan so you can easily remove the baked bars. You can also line the baking pan to be extra safe.
Fannie recommended using a 10-inch by 15-inch baking pan, so that's exactly what I did. I have not tested the recipe with a different size pan, although a 9-inch by 13-inch pan would probably work well, too. The smaller pan, however, will result in thicker (more cake-like) bars. If you have a pan that is slightly larger than 10 x 15-inches, that would likely work as well (you will just have thinner bars).
Make sure to use softened, room temperature butter to avoid a lumpy frosting.
Make sure to cool the bars completely before frosting or it will melt and probably slide off.
You can prep these bars in advance and store in a cool dry place until ready to serve or keep them in the freezer (before frosting). You can also frost the bars and keep them in the refrigerator for up to 2 or 3 days in advance.
Decorate these bars with your favorite sprinkles.