In a mixing bowl, combine flour, sugar, milk, melted butter, egg, vanilla extract, yeast, and salt.

Mix until a dough forms.

Knead the dough on a floured surface until smooth, about 5 minutes.

Let the dough rise in a warm place until doubled in size, about 1 hour.

Roll out the dough to about ½ inch thick. Use a heart-shaped cutter to cut out donuts.

Allow the cut donuts to rise for an additional 30 minutes.

Heat oil in a deep fryer to 350°F (175°C).

Fry the donuts until golden brown, about 2-3 minutes per side.

Remove donuts and place them on paper towels to drain excess oil.

Once cool, fill a donut with strawberry jam.

In a bowl, mix powdered sugar, melted butter, and vanilla extract. Add milk until desired consistency is reached.

Dip the tops of the donuts in the glaze and top with sprinkles.