Sunday Brunch: Overnight Blueberry Muffin Oatmeal

Ingredients

• 1 ¾ c. old fashioned oats
• ¼ c. brown sugar
• 1/8 tsp. kosher salt
• 1 ½ c. milk
• 1 egg
• 2 tbsp. butter, melted
• 1 tsp. vanilla extract
• 1 c. blueberries
• Vanilla yogurt for serving
• ¼ c. cold butter (1/2 stick), cut into cubes
• ¼ c. sugar
• ¼ c. flour
• 1 tbsp. maple syrup