Preheat the oven to 350 degrees F (177 degrees C).
Combine butter, condensed milk, granulated sugar, eggs, vanilla extract, and salt in a large bowl. Whisk until well incorporated.
Add the espresso powder, sweet rice flour, and baking powder. Whisk until a soft brown dough forms.
Prep 2 donut pans by greasing them with oil or butter. I used a donut pan with donut molds that are 3 inches in diameter.
Spoon the batter into a pastry bag or Ziploc bag. Pipe the donut into the donut pans.
Bake for 9-11 minutes until a toothpick comes out clean.
Let donuts cool in the donut pan for 10 minutes. Transfer to a cooling rack to cool completely.
While the donuts are cooling, make your espresso glaze. Combine coconut milk, powdered sugar, vanilla extract, and espresso powder in a bowl. Mix until combined. Set aside.
Dip the donuts into the glaze and serve!