Preheat your oven to 180°C (160°C fan) or gas mark 4. While the oven heats, peel, core, and dice the apples into 2cm chunks. They should look like small, uniform golden cubes.

Cook the apple filling. Place a large frying pan over a medium heat. Add the diced apples, honey, lemon juice, cinnamon, ginger, and nutmeg. Stir gently with a wooden spoon. After about 5 minutes, you'll hear a soft sizzle and see the apples begin to soften at the edges. The kitchen will smell warmly of spiced fruit.

Continue cooking until tender. Cook for another 4-5 minutes, stirring occasionally. The apples should be just tender when pierced with a fork but not mushy. They'll look slightly translucent and the juices at the bottom of the pan will have thickened into a glossy syrup. Remove from the heat.

Make the crumble topping. In a mixing bowl, combine the rolled oats, wholemeal flour, light brown sugar, and a pinch of salt. Add the cold, cubed butter. Using your fingertips, rub the butter into the dry ingredients until the mixture resembles coarse, damp breadcrumbs. You should see small, pea-sized clumps of butter still visible—this creates the crunch.

Assemble the crumble. Spoon the cooked apple mixture into a 20cm round or 1-litre baking dish. Sprinkle the crumble topping evenly over the apples, covering them completely. The topping should look golden and pebbly.

Bake until golden and bubbling. Place the dish in the preheated oven and bake for 18-20 minutes. You'll know it's ready when the crumble topping is a deep golden brown and you can see the apple filling bubbling up at the edges with a thick, jammy consistency. The aroma of baked apples and oats will fill your kitchen.

Rest briefly before serving. Remove the crumble from the oven and let it sit for 5 minutes. This allows the filling to set slightly, so it doesn't run everywhere when you spoon it out. The top will feel crisp to the touch.