Heat the oven to 180C/160f fan/gas 4, line the tins and make the sponge base as described in the 'goes well with' recipe (below right), but do not divide it between the tins just yet.
Halve and stone the peaches, then cut each half into 4. Toss the peaches with the sugar, then arrange in a single layer in one of the tins. Tip half the cake mix over the peaches and the other half into the second tin. Bake for 20-25 mins until cooked and golden – the tin containing the peaches may take 5-10 mins longer than the other. Leave to cool on a wire rack while you make the filling.
Whisk the clotted cream with the sugar and vanilla until stiff. Spread this over the plain sponge, then carefully top with the