This is how I dry my bananas.
First i squeeze some lemon juice in a bowl.
Next I slice the bananas a bit sideways so that each bit is oblong (not sure why I do this...)
Coat the banana bits in lemon juice then let them drip dry (via colander) next I sprinkle on them a mix of pulverized 'raw" sugar (done in a blender) and cinnamon.
cinnamon is a preservative , same for sugar.
Then I dry them for several hours using the "fruit" setting . (takes most of the day)
They come out chewy and stay good for over a year.
The really dry stuff you buy in the shops are indeed fried.
I do apples the same way, sometimes omitting the lemon dip.
Franco