Preheat oven to 425°, and line a 13x9 pan with parchment paper.
In a large bowl, add crust ingredients, and mix until formed into a thick dough.
Press dough into the bottom of the pan in a smooth, even layer.
In a separate bowl, mix apple slices and melted butter until slices are well coated. Add remaining filling ingredients (brown sugar, flour, cinnamon, nutmeg, and clove), and mix until apples are evenly coated.
Layer apple slices evenly over the crust.
Combine streusel ingredients until crumbly. Sprinkle over apple filling layer.
Bake for 30-35 minutes until edges are golden brown. Cool for at least 10 minutes, then slice into even squares.