Pour your chosen vegetable or coconut oil into a large, heavy-bottomed skillet or cast-iron pan to a depth of about 1 inch. Heat the oil over medium-high heat until it reaches 365°F on a deep-fry or candy thermometer.

While the oil is heating, wash and dry the apples. Slice each apple crosswise into ¼-inch thick rings, carefully remove the core and seeds from each slice, leaving a ring of apple flesh with a hole in the middle.

In a small, shallow bowl, combine the granulated white sugar and ground cinnamon. Whisk together until they are uniformly blended.

In a medium-sized mixing bowl, lightly beat the egg with a whisk. Gradually whisk in the milk and the vanilla extract. Add the flour, the remaining sugar, the baking powder, and the salt, whisking until a smooth batter forms.

Check that your oil has reached 365°F. Using tongs, dip each apple ring into the batter, allowing any excess to drip back into the bowl. Carefully place 3 or 4 battered rings into the hot oil, fry for 1 to 2 minutes per side until golden brown.

Remove the fried apple rings from the oil and place them on a wire rack or a plate lined with paper towels to drain for about 1 minute. Immediately dredge each ring in the prepared cinnamon-sugar mixture.

Serve the Fried Cinnamon-Sugar Apple Rings warm for the best texture and flavor. Enjoy them on their own or with a side of maple syrup or caramel sauce for dipping.