Preheat oven to 350 degrees. Grease a donut pan and set aside.

With a mixer, cream butter until light and fluffy, about 1-2 minutes. Add in sugar and beat until well combined and white in color. Add in the egg, and beat until combined.

In a separate bowl, sift together flour, baking powder, and salt. Set aside.

In a separate bowl, mix together milk and vanilla extract.

Alternately stir the flour mixture and milk mixture into the butter mixture, beginning and ending with the flour mixture.

Once just combined (be careful not to overmix), scoop batter into a piping bag and fill each donut cavity about 3/4 of the way full.

Bake for 10-12 minutes, or until an inserted toothpick comes out clean.

While cooling, melt the butter in a microwaveable bowl or in a pot over the stovetop.

Mix the sugar and cinnamon together in a separate bowl.

Once the donuts are cool enough to handle, dunk both sides of the donut in the melted butter. Immediately roll the donuts in the cinnamon sugar mix, making sure it is well-coated. Allow to finish cooling on a wire rack.

With a mixer on medium speed, beat the heavy cream until it begins to thicken. Add in powdered sugar and vanilla, and continue to beat until it reaches a whipped-cream consistency.

Slice donuts in half, spread whipped cream over one of the halves, add sliced strawberries, and top with the other donut half!

Enjoy!