Preheat oven to 190°C.
In a small pan, melt 20 g of the butter over a moderate heat until it turns pale nut-brown in colour. Leave it to cool for a few minutes, then use this to generously butter your friand or muffin tins. Place the tins in the fridge to go cold then dust lightly with a little extra flour and again place in the fridge until you need them. You can avoid this step by baking your friands in paper muffin cases - in which case you will only need 140 g of butter.
Place the remaining butter in the pan and melt it without it getting too hot.
Place the almonds, the flour and 140 g of the sugar in a food processor and blitz to a not-too-fine crumb. Tip this mixture into a medium-sized bowl and make a well in the centre. Pour the butter into the centre and work it all together, then stir in the chopped figs and dates.
Whisk the egg whites with the remaining 60 g sugar and the salt to form soft peaks. Quickly mix one-third of this into the almond mixture, then fold the remaining two-thirds in. Spoon the mixture into the prepared moulds and bake for 25-30 minutes, until a skewer inserted comes out barely moist and they’ve turned golden. Leave to cool for 10 minutes before gently tapping out and cooling on a cake rack.
These are best eaten straight away, but they keep really well in an airtight container for 2 days.