Prepare the peach layer: Take the drained peach slices and chop them into small, bite-sized pieces — about 1cm cubes. You're looking for a chunky texture here, not a puree. Place the chopped peaches in a small bowl with the lemon juice and caster sugar. Stir gently until the sugar has dissolved, then set aside. You should see the juices beginning to run and the peaches turning slightly glossy.

Toast the almonds: Tip the flaked almonds into a dry frying pan over a medium heat. Shake the pan every few seconds. After about two minutes, you'll smell a warm, nutty aroma and the almonds will turn a light golden brown with darker edges. Tip them immediately onto a plate to cool — they'll continue toasting from the residual heat.

Make the mousse base: In a large mixing bowl, beat the softened cream cheese with a wooden spoon until it's smooth and silky, with no visible lumps. Add the sifted icing sugar and vanilla extract, then beat again until the mixture is pale and fluffy. This should take about a minute — you'll see the colour lighten and the texture become airy.

Whip the cream: In a separate bowl, pour in the double cream. Whisk vigorously until it forms soft peaks — when you lift the whisk, the cream should hold its shape briefly before gently flopping over. Be careful not to over-whip; if the cream looks grainy and separated, you've gone too far. You want it thick but still luscious and smooth.

Fold together: Add the whipped cream to the cream cheese mixture in three additions. Using a spatula, fold gently — cut down through the centre, sweep along the bottom, and bring up over the top. Repeat until no white streaks remain. The finished mousse should look pale, airy, and billowy, like a soft cloud.

Assemble the first layers: Take a large glass serving bowl or trifle dish. Spread a thin layer of mousse across the bottom — about 1cm thick. Dip each sponge finger into the reserved peach juice for about three seconds — you want them softened but not soggy. Arrange a single layer of soaked biscuits over the mousse, breaking them to fit if needed.

Build the layers: Spoon half the chopped peaches over the biscuits, then sprinkle with a third of the toasted almonds. Spread half the remaining mousse on top, smoothing it gently with the back of a spoon. Repeat with another layer of soaked biscuits, the rest of the peaches, another third of almonds, and finish with the remaining mousse.

Chill and garnish: Cover the dish with cling film and refrigerate for at least one hour — longer is better. Before serving, scatter the remaining toasted almonds over the top and add a few fresh mint leaves if you're using them. The mousse should be firm enough to hold its shape when spooned out, but still light and creamy on the tongue.