1/3 cup white granulated sugar
1/3 cup packed light or dark brown sugar
1/4 teaspoon salt
1 tsp cinnamon
1/2 cup old-fashioned or quick-cooking oats
1/2 stick (or 1/4 cup) butter, sliced
2 Tbsp pecans, chopped (optional)
2 Tbsp almonds, chopped (optional)
Stir in the oats and, if you're using them, nuts.
Spread evenly over the fruit mixture in the crockpot. Leave the lid off for the last 30 minutes or so of cooking time, to allow the topping to become a little crunchy around the edges.