Preheat your oven to 350°F and lightly butter a 9x13-inch baking dish. This ensures even baking and easy release after the crumble finishes cooking.
Combine peeled apple slices in a large bowl with granulated sugar, brown sugar, vanilla extract, cinnamon, and nutmeg. Toss until every slice is evenly coated, then spread the filling into your prepared baking dish.
In another bowl, mix rolled oats, all-purpose flour, and salt together until combined. This dry base prevents clumping in the crumble topping.
Add softened butter and packed brown sugar to the oat mixture, then drizzle with honey and fold in chopped pecans. Work the mixture with a fork until crumbly yet slightly moist—this texture ensures crispy, golden results.
Spread the apple crumble recipe topping evenly over the apple filling without pressing down. Bake for 35 minutes until the topping is golden brown and apples are tender.
Remove from the oven and let cool for 10 minutes before serving. This resting period allows the filling to set slightly while the topping remains crunchy.