• Butter your pie dish.
• Heat your oven to 190°C/170°C fan/375°F/Gas mark 5
• Place a large baking tray in the oven to heat.

Crumble topping

• Sift your flour and salt together and add to your food processor bowl.
• Give the flour a whizz just to ensure it is evenly spread within the food processor bowl.
• Add your grated butter and pulse several times until the butter is mixed in and no large lumps remain.
• Add in your remaining ingredients and again pulse just until combined. The mixture should look like sand when ready. Make sure you don't overmix or it will start to clump together.
• Pop in the fridge to chill.

Apple filling

• Add your lemon juice to your bowl along with about 2 litres of cold water.
• Peel and core one apple at a time.
• Slice the apple into 1cm slices and place in the water to stop them from oxidising.
• Once all your apples are prepared, drain them and them pat them dry with your clean tea towels.
• Dry your bowl and return the dried apples to it.
• Pop your Biscoff® spread in a microwave just until melted, about 20 seconds is usually enough.
• Add all of your melted Biscoff® spread and remaining ingredients to your apples and give everything a good mix. I use 2 wooden spoons to do this, like tossing a salad.
• Place each piece of apple, piece by piece, flat side down, into your prepared dish. Make sure that you cover all of the base.
• Continue to build up the apple slices until they have all been used. Ensure, as much as possible, that the top of the apple stack is level and that the apples fill every gap possible.
• Tip your crumble mix over the apples and spread it out to cover them all.
• Press down just a little to compress very slightly.
• Rough the top of the crumble up by dragging a fork across it.
• Sprinkle over your demerara sugar if using.
• Place on the preheated baking tray and bake for 40-45 minutes.
• When done, the crumble should be lightly browned and the apple should have just a little resistance when you place a skewer through it.
• Leave to cool and settle for 10 minutes before serving.
• Serve with my custard recipe or vanilla ice cream.