Preheat your oven to 350°F (175°C). Grease your donut pan with non-stick spray.

In a large mixing bowl, whisk together the flour, 3/4 cup of sugar, baking powder, and salt until well combined.

In another bowl, combine the milk, melted butter, eggs, and vanilla extract. Mix until smooth.

Gradually add the wet ingredients to the dry ingredients, stirring gently until just combined. Do not overmix; this will keep the donuts fluffy.

Spoon the batter into the prepared donut pan, filling each cavity about 2/3 full.

Bake for 12-15 minutes or until the donuts are lightly golden and a toothpick inserted comes out clean.

Remove from the oven and allow to cool in the pan for 5 minutes before transferring to a cooling rack.

In a medium mixing bowl, beat the softened cream cheese until smooth using an electric mixer.

Add the sour cream, powdered sugar, and vanilla extract. Mix until creamy and well combined.

Fold in the peach preserves and cinnamon gently until evenly distributed.

Transfer the cheesecake filling to a piping bag or a zip-top bag with the corner snipped off for easy filling.

Once the donuts are completely cooled, use the piping bag to fill each donut with the cheesecake filling. Insert the tip into the side of the donut and squeeze gently.

For the glaze, whisk together the powdered sugar, milk, vanilla extract, and cinnamon in a small bowl until smooth.

Dip the top of each filled donut into the glaze, allowing excess to drip off. Place back on the cooling rack to set.