Apple & Crumb Topping
In a medium bowl, toss the diced Granny Smith apples with melted butter, brown sugar, cinnamon, vanilla extract, salt, and flour. In a large mixing bowl, combine flour, oats, brown sugar, granulated sugar, cinnamon, nutmeg, and salt. Add softened butter pieces and mix using your fingers until the mixture forms coarse crumbs with some larger clumps.