Cream butter, sugar and ground almonds together. Put a teaspoon of the mixture into 24 shallow patty tins or 2 × 18 cm/7 inch sandwich tins. Bake at 180°C/350°F/regulo 4 for 20–30 minutes approx., or until golden brown. The tart or tartlets are too soft to turn out immediately, so cool in tins for about 5 minutes before removing from tins. Do not allow to set hard or the butter will solidify and they will stick to the tins. If this happens pop the tins back into the oven for a few minutes so the butter melts and then they will come out easily. Allow to cool on a wire rack.
Just before serving, arrange slices of peeled peaches or nectarines, whole raspberries, or peeled and pipped grapes on the base. Glaze with red currant jelly (red fruit) or apricot glaze (green or yellow fruit). Decorate with rosettes of whipped cream and garnish with lemon balm or sweet geranium leaves.