Preheat the oven to 180c/160c fan/350f/gas mark 4 and add cupcake or muffin cases to a 6 hole muffin tin.
Add the milk and vinegar (or lemon juice) to a jug, mix and set aside.
Now add the flour, sugar, baking powder and salt to a mixing bowl.
Mix the dry ingredients well.
Add the vanilla extract and oil to the milk, mix and pour into the dry ingredients.
Fold the wet ingredients into the dry until just combined. Be careful not to over mix. Don't worry about little bits of flour.
Use an ice cream scoop or spoon to add some batter to each muffin case, you want to half fill them.
Add a teaspoon of jam to each, then top with the rest of the batter and sprinkle with sugar.
Bake for 20-25 minutes until baked and lightly golden. You can insert a skewer or toothpick. If it's clean of batter, then it's baked through. If not give it a few more minutes.
Remove from the oven and leave to cool in the tin. Once they are just warm, you can brush with maple syrup and sprinkle with or dunk in sugar for that sugary doughnut topping.
Enjoy!
Notes
These type of muffin are best eaten on the day they are made.They are at their very best when they are freshly made, but they can be kept in an airtight container for a few days.You can add your favourite jam or chocolate spread as a filling.You can skip the sugar on top if you like, but it does give that doughnut finish.