sit and stay awhile apple crisp

bake in an 8×8 baking dish or double the recipe and bake in a 9×13 dish
Filling:5 to 6 medium-size apples, peeled, cored and cut into 1/4-inch slices. (About 7.5 cups)
3 tbsp granulated sugar
1.5 tsp cinnamon

Topping:
1 1/3 cups all-purpose flour
1 1/3 cups lightly packed brown sugar
1/2 tsp ground cinnamon1 stick unsalted butter, well-softened
2/3 cup finely chopped pecans (optional)
1/3 cup quick oats