Bacon and Egg Breakfast Muffins

Bahan-bahan (4 porsi)

• 150 g / 5oz bacon (, chopped (I use lean))
• 1 cup green onion (, finely sliced (2 stems))
• 1 cup (100g) cheddar cheese (, shredded (or other of choice))
• 1 1/2 cups (225g) flour (, plain / all purpose)
• 1 1/4 tsp baking powder ((Note 1))
• 1/4 tsp baking soda ((aka bicarbonate soda, Note 1))
• 2/3 cup (165 ml) milk (, full or low fat)
• 1/2 tsp white vinegar ((Note 2))
• 1/2 tsp salt
• 2/3 cup sour cream or plain yoghurt (, preferably full fat)
• 3 tbsp vegetable oil ((or other neutral flavoured oil))
• 1 egg
• 4 eggs
• 2 tbsp melted butter