Grape muffins

This is a recipe I adapted from 101 Gluten-Free Recipes June 2014. They were supposed to be strawberry flavoured, but I discovered the strawberries had gone off at the very last minute, so I included grapes instead :-).

Ingredients:
400g gluten free flour (I use Doves Farm white self-raising blend, with some raising agents and xanthan gum already mixed in)
1 1/2 teasopoons baking powder
160g sugar (I use glucose)
2 eggs
200 ml soya yoghurt
60 g butter, melted
1 tsp vanilla extract
1 tsp strawberry flavouring
300 g grapes, cut into quarters

Mix flour, sugar and baking powder in a bowl. In a separate bowl, whisk the eggs and then add the soya yoghurt, butter, and vanilla and strawberry flavourings. Mix the dry and wet ingredients together - add more yoghurt if the mixture is too dry. Add the grapes. Spoon into muffin cups and bake at 150C for 30ish minutes (original recipe states 190C for 15-18 minutes, but this results in burned glucose if you opt for this sugar.)