Heat the oven to 180°C, 160°C fan, gas 4. Lightly grease a 6 x 75ml, heart-shaped baking moulds.
Melt the butter over a medium heat then leave over the heat for 1-2 minutes until the melted butter turns golden and smells nutty. Leave to cool.
In a medium bowl, beat together the icing sugar, flour, ground almonds and egg whites.
Add the cooled melted butter and mix well. Spoon the mixture into the moulds and spread out a little.
Bake for about 15 -18 minutes. Leave to cool for 5 mins, then turn out onto a wire rack and leave to cool completely.
Using a sharp knife, make a hole into top of each cake and fill generously with Bonne Maman Strawberry Conserve. Sprinkle with the pistachios.
The baked Financiers will freeze well for up to a week before filling and serving.