Preheat the oven to 325˚F. Lightly spray a doughnut pan with cooking spray and set aside.
In the bowl of a stand mixer, cream together the milk, Nutella, sugar, eggs, butter and vanilla paste.
In a seperate bowl, mix together the flour, baking soda and salt.
Slowly mix in the dry ingredients into the wet ingredients until fuly incorporated.
Pour the mixture into a large ziplock bag and cut a corner. Pipe the mixture in the prepared oven for 12-15 minutes, or until a toothpick inserted comes out clean.
Remove from the oven and allow to cool on wire racks.
Glaze: In a medium bowl, mix together the glaze ingredients until smooth.
Dip one side of the doughnuts in the glaze, twirl it around and place it back on the wire racks to dry completely.