Blueberry muffins

I am soooo proud of myself in my first trial of the blueberry muffins. The recipe as follows:

Ingredients
(Makes about a dozen muffins with cupcake liner measuring 5cm in diameter by 3cm in height )
- 1 1/2 cups* (190g) plain flour
- 1 1/2 eggs, beaten
- 1/2 tbsp baking powder
- 1 cup (225g) caster sugar
- 150g blueberries
- 1/2 cup (125 ml) milk
- 1 tsp vanilla essence/extract
- 65 grams butter, cut to small pieces and melted or softened at room temperature

Directions
1. Sift flour, baking powder and sugar together, and mix well.
2. Add in milk, vanilla extract, eggs and butter and stir until just blended (and lumpy). Be careful not to over mix as it will result in a tough texture.
3. Fold in the blueberries into the mixture. Place baking cases in muffin tins. Spoon the mixture into the cases till almost full.
4. Bake for 20 minutes in preheated oven of 200C or until slightly golden brown.