Pre-heat oven to 180°C. Grease a 6 hole muffin pan

Sift flour into a bowl, add a pinch of salt and the caster sugar. In a jug, combine the oil, egg, buttermilk and vanilla extract. Add to the dry mixture and stir to only just combine

Place a heaped tablespoon of the mixture in each muffin hole and make an indent in the centre. Fill each indent with a generous 1/2 teaspoon of IXL jam. Cover the jam with the remaining muffin mixture, ensuring jam is covered

Bake for 20 minutes. Remove from oven and set aside to cool slightly

Meanwhile, melt butter. Combine the extra sugar and cinnamon in a large bowl. When the muffins are cool enough to handle, brush each muffin with the melted butter, then roll in the cinnamon sugar. Serve warm