When Mama holds up a magnifying glass during a cooking task/step, that means there is alternative input to the normal touchscreen interface. Additionally, during "Let's Cook" when you are attempting to fully do a recipe, you will see zero, one, or more magnifying glasses with a "!" mark in them in the upper left corner of the instructions (similar to the star, located in the lower-left corner).
The alternative inputs vary, and if there are more than one magnifying glasses, that means there are multiple inputs, usually for different phases or tasks. At first, they will appear grey on the instructions; completing them during a task will turn the exclamation mark red to indicate you have done the input before.
As an example, when grilling shrimp on the woodburning stove, you normally have to slide over the fan under each shrimp to get the fire going. However, if you blow into the microphone, it will instead use a giant fan on all four fires, which will dramatically shorten the time required for the task.
Another example is with Salisbury Steak. The first task, "Grind the meat!", has two magnifying glasses. This task has you shoving meat down by sliding the stylus downward three times, then rotating the handle to grind the meat. The first input is to slide down on the analog pad. The second is to rotate the analog pad like you would with the stylus.
If you do a recipe and get one of the New! inputs during a step, then the recipe will show that magnifying glass icon on the bottom left of the recipe, just like the Medal that shows on the upper right. If you perform all of the New! inputs, then the magnifying glass will become golden.
Some sample inputs I have found:
- Physically move the 3DS (grating bread and tapping the lid)
- Move the analog pad
- Blow into the microphone
- L/R Shoulder buttons (Mustard and Ketchup; can do BOTH at the same time!)