Blueberry muffins

For ➊➋ muffins 
100 g butter 
200 ml milk 
grated lemon zest 
2 eggs 
125 g granulated sugar 
1 ts vanilla sugar 250 g flour 
2 ts baking powder 
1 pinch salt 
125 g blueberries (fresh or frozen)

Preheat the oven to 175 ° C for large muffins and 200 ° C for small muffins. 
Melt the butter and stir in the milk and the grated lemon zest. Beat the eggs with the crystal and vanilla sugar until light and fluffy. Stir the butter mixture into the egg mixture. Sift the flour with the baking powder and salt and carefully fold this into the butter-egg mixture. 
Place paper caisses in a muffin tray. 
Spoon some blueberries in and fill the ⅔ molds with the dough. Bake large muffins 20 m and small 12-15 m in the center of the oven. 
A skewer that you stick in the middle should come out dry.