Oven temperature too low
Follow bake temperature and time recommendation on package label. Have oven checked for accuracy.
Under baked
Bake to a golden brown color
Over measurement of water
Use the proper amount of liquid. When possible, use a scale to weigh the water.
Oven temperature too high
Follow label directions for proper oven temperature. Check temperature for accuracy.
Under measurement of water
Underbaked
Pan not sprayed or sprayed properly
Spray sheet pan well
No parchment paper on pan
Place one sheet of parchment paper on sheet pan
Overmeasurement of water
Pan is too small for the amount of filling
Select proper pan size for the amount of filling. If doing a full batch, use a full sheet pan.
Uneven heat and air circulation in oven
Rotate pans one half (180°) after 10 minutes (Fudge Nut Bar) or 15 minutes (Lemon Bar) of baking. Check air baffles in convection oven to ensure even air flow.
Opening oven door too frequently
Open oven door only when necessary, especially when baking in a convection oven.
Oven shelf not level
Have shelves checked. Rotate bars in a convection oven one-half turn (180°) after 10 minutes (Fudge Nut Bar) or 15 minutes (Lemon Bar) of baking.
Filling not leveled properly
Use an offset spatula to smooth out filling surface.
Pans not rotated in a convection oven
Rotate bars in a convection oven one-half turn (180°) after 10 minutes (Fudge Nut Bar) or 15 minutes (Lemon Bar) of baking.
Pans are bent
Do not use warped or bent pans for baking bars.
Uneven heat circulation
Have air baffles checked in a convection oven to ensure even air flow.
Pans too close together in oven
Do not allow pans to touch each other in oven.
Follow package directions for proper bake temperatures. Check oven temperature for accuracy.
Follow package directions for proper amount of water. If possible, use a scale to weigh the water.