Bakery Style Jumbo Blueberry Muffins with Streusel Topping

Ingredients

• 3 tbsp unsalted butter, melted
• 1/3 cup all-purpose flour
• 1/4 cup granulated sugar
• 1/2 cup (1 stick) unsalted butter, melted
• 1 cup (200g) granulated sugar
• 2 large eggs
• 1/2 cup (80g) sour cream or plain greek yogurt
• 1 cup milk (240g), whole milk or non-dairy milk
• 1 tsp vanilla extract
• 3 cups (360g) all-purpose flour
• 2 tsp baking powder
• 1/2 tsp baking soda
• 1/2 tsp salt
• 1/2 tsp cinnamon (optional)
• 2 cups fresh or frozen blueberries (if frozen, do not thaw)