Preheat oven to 180°C. Grease a 6 hole doughnut pan generously with butter.
Sift flour and salt into a medium bowl and add sugar. Pour milk in a small jug, add vinegar and set aside for one minute. Whisk in egg and oil.
Pour egg mixture over dry ingredients and whisk until combined.
Using a jug, pour batter into prepared tin about 2/3 full to leave room for rising. Bake for 10 minutes or until lightly golden. Cool on a wire rack.
While doughnuts are baking, make maple glaze by melting butter and maple syrup in a small saucepan over low heat. Add cream, bring to the boil and simmer for five minutes, whisking occasionally, until thickened. Remove from heat and pour into a small bowl, add vanilla and set aside to cool.
When doughnuts have cooled, dip in maple glaze and sprinkle lightly with pink sea salt flakes.
