Step 1: Preheat your oven to 350°F (175°C) and grab your 12-cavity donut pan. Give it a light grease to make sure your beautiful donuts pop right out.
Step 2: In a large bowl, whisk together your pancake mix, 3 tablespoons of brown sugar, 1 teaspoon of cinnamon, and ½ teaspoon of nutmeg. Just a quick whisk to combine all those dry goodies.
Step 3: In a separate, smaller bowl, whisk together the milk, egg, and 2 tablespoons of melted butter.
Step 4: Pour the wet ingredients into the dry ingredients. Stir them together until they are just combined. Resist the urge to overmix; a few lumps are totally fine!
Step 5: Gently fold in your finely diced apples. Make sure they're evenly distributed throughout the batter.
Step 6: In a small bowl, combine the ¼ cup softened butter, ½ cup brown sugar, ½ cup all-purpose flour, ½ teaspoon cinnamon, and 1 teaspoon nutmeg. Use a fork or your fingertips to mix until it forms a lovely crumbly texture.
Step 7: Spoon your donut batter into the prepared donut pan cavities, filling each one approximately ¾ full.
Step 8: Generously sprinkle that delicious crumb mixture over the top of each donut. Don't be shy!
Step 9: Bake for 12–15 minutes, or until a toothpick inserted into a donut comes out clean. You're looking for a lovely golden brown.
Step 10: Allow the donuts to cool in the pan for about 5 minutes. They’ll be a little delicate when warm.
Step 11: Carefully transfer them to a wire rack to cool completely.
Step 12: Once they’re cool (or just warm enough to handle, if you can’t wait!), sprinkle them with powdered sugar before serving. Enjoy your homemade masterpiece!