Wash and peel the apples. Cut them into 0.25-0.5 inch slices. You can use a mandolin for even thin slices. Remove the seeds and cores to get nice apple rings with an easy-to-use apple corer or a small cookie cutter.
Prepare the pancake batter
In a large bowl mix together the flour, the milk, and the psyllium husk thoroughly with a whisk and let it sit for 5 minutes until the husk thickens the batter.
Dip the apple rings in the batter one by one and fry them as they were pancakes. Flipping them after a couple of minutes to have both sides golden brown.
While still hot, dip them into cinnamon sugar. (If you wait, and the apple donuts cool down, the sugar won't stick to them.) Serve it with a scoop of vanilla ice cream, caramel sauce or melted chocolate. Enjoy!
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Notes
Which apples to fryLarge, firm and tart apples like Granny Smith or Pink Lady or anything similar.Top tips for making perfect Fried Apple Rings
You need to fry on low-medium heat, so the apples will be cooked. Firm and tart apples tend to remain crunchy if you cut them too wide or cook them for too short.
Even if the apples remain a bit crunchy (but you have to take them out because the pancake batter is already golden brown), don't worry, they will soften on room temperature while they are resting. You can even cover them to make sure they do soften.
I read somewhere ages ago that you can prepare apples for baking if you drop them in hot water for 5 minutes. In that way, the apples will not release any further liquid while baking (no pies with soggy bottom) and the slices soften up a bit as they are pre-cooked so to speak. I tried this method with these apple rings and there were no crunchy apples at all.
For a more frugal approach, you can use ½-1/2 water and milk.