Best Dutch Apple Pie Recipe - How to Bake Dutch Apple Pie

Ingredients

• 1 1/2 c. all-purpose flour, plus more for surface
• 1/2 c. unsalted butter, cut into 1/2" pieces
• 1 tbsp. granulated sugar
• 1/4 tsp. kosher salt
• 1/2 tbsp. apple cider vinegar
• 4 tbsp. ice water (or more, if needed)
• 3 c. Granny Smith apples, peeled, cored, and cut into medium pieces
• 1/3 c. granulated sugar
• 2 tbsp. all-purpose flour
• 1/2 tsp. kosher salt
• 1/2 tsp. ground cinnamon
• 3/4 c. sour cream
• 1 egg
• 2 tsp. vanilla
• 3/4 c. firmly packed brown sugar
• 1/4 c. granulated sugar
• 1/2 c. all-purpose flour
• 1/4 c. old-fashioned oats
• 1/4 c. toasted and chopped walnuts
• 6 tbsp. butter, softened