Crush the biscuit base. Place the digestive biscuits in a sealed plastic bag and bash them with a rolling pin until they become fine crumbs — you want a sandy texture with no large chunks. Alternatively, pulse them in a food processor for a few seconds. The crumbs should feel like damp sand when you pinch them.

Mix the butter and crumbs. Pour the melted butter into the biscuit crumbs and stir with a fork until every crumb is coated. The mixture will smell rich and buttery, and it should clump together when pressed in your fist. Divide this evenly between 6 small cups or ramekins — about 2 tablespoons each — and press down firmly with the back of a spoon. The base should feel compact and solid, not loose.

Beat the cream cheese and sugar. In a large mixing bowl, beat the softened cream cheese with the caster sugar and vanilla extract using a hand mixer on medium speed. Beat for 2-3 minutes until the mixture is completely smooth, pale, and free of any lumps — you should see no white specks of cream cheese. The texture will look like thick, glossy frosting.

Whip the double cream. In a separate bowl, whip the double cream until soft peaks form. You know it's ready when you lift the whisk and the cream holds a gentle peak that flops over slightly. Be careful not to overwhip — if it looks grainy or like butter, you've gone too far. The cream should feel light and airy.

Fold everything together. Gently fold the whipped cream into the cream cheese mixture using a rubber spatula. Add the lemon juice at this stage too. Fold with a gentle cutting motion, scraping the bottom of the bowl, until no white streaks remain. The final mixture should be silky, thick, and mousse-like — it will hold its shape when spooned.

Fill the cups and chill. Spoon the cheesecake filling over the biscuit bases, dividing it evenly. Smooth the tops with the back of a spoon. The filling should be level and flush with the rim of each cup. Place the cups in the fridge for at least 2 hours — the tops will feel firm to the touch when set, and the filling will no longer jiggle when you tap the cup.

Prepare the berries. While the cups chill, place the mixed berries in a small saucepan with the icing sugar and 1 tablespoon of water. Heat gently over a medium heat for 3-4 minutes, stirring occasionally, until the berries soften and release their juices. The mixture will turn a deep ruby red and smell intensely fruity. If you want a thicker sauce, stir in the cornflour mixed with a splash of cold water and cook for another minute until glossy. Let the berries cool completely before topping the cheesecakes.