Whisk together lukewarm milk, egg, and melted butter until smooth. The milk should be about 110°F (43°C) to activate yeast.

In a separate bowl, whisk together all-purpose flour, sugar, and instant yeast until light and aerated.

Gradually add dry ingredients to wet mixture, stirring gently until a soft, slightly sticky dough forms.

Transfer the dough to an oiled bowl, cover with a damp cloth, and let it rise in a warm place for 1.5 to 2 hours.

Roll out the risen dough on a floured surface to about ¼ inch thickness.

Cut the dough into shapes using a donut cutter or two round cookie cutters.

Heat vegetable oil in a deep pan or large pot to 170-180°C (340-360°F).

Gently fry the donuts in hot oil for 2-3 minutes on each side until golden-brown.

Whip the heavy cream with sugar until stiff peaks form.

Fill cooled donuts with whipped cream using a piping bag or spoon and dust with powdered sugar before serving.