Preheat oven to 180°C/350°F and have a donut mold ready. (I used a silicone mold from Amazon)

Mix the flour, baking powder and sugar together in a bowl.

Add the melted butter, milk and vanilla and fold in gently.

Carefully spoon the mixture into the donut pan (will make roughly 8 donuts).

Bake for 25-30 minutes until golden brown and leave to cool completely in the pan.

Remove donuts from the pan and decorate. See post above for frosting ideas and recipes.

Mix the milk and lemon juice/ vinegar together using a fork then set aside. (this will make vegan buttermilk)

In a separate bowl, mix together the flour, baking powder and sugar.

Add in the melted butter and the buttermilk. Combine gently with a metal spoon, then use your hands to form a soft dough.

Lightly flour your surface and roll out the dough to about 2 inches thick. Cut out donut shapes using a cookie cutter or bottom of a small glass. Re-roll the dough and repeat until it is all used. (will make 8-10 donuts)

Fill up a pot or pan with about 2-3 inches of oil and put on medium-high heat. 

You can test if the oil is hot enough by placing a small piece of dough into the pan. If the oil is ready, the dough should immediately start bubbling and float to the top.

Place your donuts, a few at a time, into the oil using a spatula. Fry for around 1 minute on each side, or until golden brown. Remove the donuts and place them on some kitchen paper to cool completely.

Ice or fill your donuts however you like. See post above for some frosting ideas and recipes.