Preheat your oven to 400°F. If you have a convection option, use that for even baking. Prepare a baking sheet by lining it with heavy-duty nonstick aluminum foil for easier cleanup.
Next, add the diced sweet potatoes to the baking sheet. Drizzle them evenly with the coconut oil, then season with kosher salt and freshly ground black pepper. Toss everything together with your hands until the sweet potatoes are well coated.
Bake the sweet potatoes for about 25 to 30 minutes. You want them to be about 80% cooked through—softening but not fully tender yet. They should look slightly caramelized and have a lovely golden hue.
While the sweet potatoes are baking, prepare your topping. In a medium bowl, combine the melted butter, brown sugar, flour, and cinnamon.
Fluff the mixture with a fork until it forms small clumps, resembling pea to grape sizes. If the mixture seems too wet, gradually add more flour until you reach the desired clumping texture.
Once the sweet potatoes are ready, transfer them to a 9×13-inch casserole dish. Spread them out evenly so they form a nice base.
Now, add the diced apples directly over the roasted sweet potatoes. Sprinkle with an extra dash of cinnamon and drizzle with more coconut oil if you like.
Evenly top the sweet potatoes and apples with your clumpy mixture from earlier. Make sure it’s well-distributed to ensure every bite has that delightful topping.
Reduce the oven temperature to 375°F and return the casserole to bake for another 30 minutes. Look for the apples to be tender and the topping to be lightly golden brown and set. The sweet potatoes should be fully cooked through.
Serve immediately while it’s warm, and watch as your loved ones dig in with delight!
