In a medium bowl, whisk together your dry ingredients: flour, baking powder, cinnamon, and salt. Give it a good mix so everything is evenly distributed.
In a separate bowl (or a large measuring cup), whisk together the eggs, milk, and melted butter until they're well combined.
Pour the wet ingredients into the bowl with the dry ingredients. Stir gently with a spoon or spatula until just combined. Don't overmix! A few lumps are totally fine – overmixing develops the gluten and can make your fritters tough.
Now, carefully fold in your diced fresh peaches. Stir just enough to distribute them throughout the batter. You want plenty of peachy goodness in every bite!
Pour about 1-2 inches of oil into a heavy-bottomed pot or a deep skillet. Heat the oil over medium heat until it reaches about 350-375°F (175-190°C). If you don't have a thermometer, you can test it by dropping a tiny bit of batter in – it should sizzle and float to the top within a few seconds.
Using two spoons (or a small cookie scoop), carefully drop spoonfuls of batter into the hot oil. Don't overcrowd the pan – fry just a few at a time so the oil temperature doesn't drop too much. They should puff up and turn golden brown quickly.
Fry for about 2-3 minutes per side, flipping halfway through, until they are golden brown and cooked through. Use a slotted spoon or spider to carefully remove the fritters from the oil and place them on a wire rack set over paper towels to drain off any excess oil.
While the fritters are draining (or cooling just slightly), whisk together the powdered sugar and a tablespoon of milk in a small bowl. Add more milk just a tiny bit at a time until you have a smooth glaze that's thin enough to drizzle but thick enough to coat the fritters.
You can dip each fritter into the glaze or simply drizzle it generously over the warm fritters. Serve them immediately while they're warm and crispy outside, soft inside, and absolutely irresistible!