Apple Crumb Muffins

Bahan-bahan (12 porsi)

• 2 cups all-purpose flour
• 2 teaspoons baking powder
• ½ teaspoon salt
• 1 cup whole milk
• ¼ cup vegetable oil
• 1 large egg
• ½ cup granulated sugar
• 1 teaspoon vanilla extract
• 1 ½ cups Granny Smith apples (peeled and diced (about 2 apples))
• ⅓ cup brown sugar
• 1 teaspoon ground cinnamon
• ⅔ cup all-purpose flour
• 1 dash salt
• ¼ cup unsalted butter (melted)