Step 1

Preheat the oven to 350ºF/175ºC.

Step 2

Clean the apples and cut off the top 1-inch of the apple. Then, using an apple corer, spoon, small ice-cream scoop, or melon baller, remove the core and pulp from the middle of the apple (refer to images for how much to remove – I like to leave at least ½ inch of flesh on all sides).Alternatively, you can slice the apples in half, remove the core, and then simply pile the cinnamon oat ‘streusel’ topping over the apple halves (no need to scoop out the middle and mince the flesh).

Step 3

Discard the seeds, then place all the remaining pulp into a medium bowl after mincing it with a knife.

Step 4

Roughly chop the walnuts and add them to the bowl with the minced apple along with the oats, spices, oil (or butter), and sweetener of your choice. Mix well until thoroughly combined.

Step 5

Divide the mixture between the cored apples and then place the tops back on the apples (this will keep the top moist- alternatively, you can top each apple with a tiny pat of butter – ¼ tbsp).If you have any leftover oat mixture, you can use it to make simple overnight oats or save it in the fridge to top yogurt bowls, etc.

Step 6

Oven-Baked ApplesTransfer the apples to a baking tray in the center of the oven. Then bake for between 20-25 minutes, or until the apples are tender.At 25 minutes, my stuffed apples still have a little "bite," the way I prefer. However, this will vary depending on the size and type of apples used. Many take closer to forty minutes. If you like them to be softer, simply bake for longer (up to 50 minutes).Air fryer Baked ApplesPlace the apples (either whole stuffed apples or halved "topped" apples) in your air fryer basket (no need to keep lots of space between as their closeness will help them "steam" and cook – optionally, you could also pour 1/2 cup of water into the bottom of your air fryer basket).Cook in the air fryer at 350ºF/175ºC for 15 minutes or until tender (can take up to 20 minutes for perfectly tender air fryer baked apples).

Step 7

Make ahead: you can prepare the "stuffing" (minus the apple) several days in advance. You could also core the apples and stuff them, then cover with plastic wrap until you're ready to bake. However, if you're doing the latter, you'll need to rub some lemon juice over the cored apple interior and mixed into the minced apple - to stop them browning.Store: Allow the baked apples to cool and then transfer the leftovers to an airtight container in the refrigerator for up to 4-5 days.Freeze: frozen and thawed apples will become mushier in texture, and the nuts will become softer, too. However, if you don't mind this, you can store the healthy baked apples in an airtight container in the freezer for up to 2 months. Thaw the apples in the fridge overnight, then reheat.Reheat: place the stuffed baked apples back in the oven and bake at 350ºF/175ºC for 15-20 minutes, or in the air fryer for 5-10 minutes until warmed through. You could also heat it in the microwave (between1-2 minutes), though it will become mushier this way.