Oatmeal Flax Blueberry Muffins

Bahan-bahan (6 porsi)

• 1/2 cup rolled oats or old fashioned oatmeal
• 1/2 cup buttermilk (or regular milk + 1 teaspoon vinegar)
• 1 1/2 tablespoons salted butter, melted
• 1 egg
• 1/3 cup brown sugar
• 1/2 teaspoon vanilla
• 1/2 cup + 1 tablespoon flour
• 1 heaping tablespoon ground flaxmeal
• 1/2 teaspoon baking powder
• 1/2 teaspoon baking soda
• 1/4 teaspoon salt
• 1/2 cup fresh blueberries
• 1 tablespoon cold butter, cut into small pieces
• 3 tablespoons flour
• 1 tablespoon brown sugar
• 1/4 cup powdered sugar
• 1/2 tablespoon milk