To make the caramel, first measure out all the components so you are ready to go (it happens quickly!).

Heat the sugar in a medium pot over medium-high heat, stirring constantly with a wooden spoon. It will form clumps and start to melt into an amber liquid - watch carefully, ensuring it doesn’t catch/burn.

When it is melted and golden-brown, add the butter and whisk until combined (this may take a couple of minutes). Be careful as the caramel will bubble and steam vigorously.

Drizzle in the cream slowly, again whisking constantly until fully combined (1-2 minutes). Remove from the heat.

Stir in the vanilla and salt to taste. Put in the fridge to cool for at least 1-2 hours, until cold.

Preheat oven to 180°C.

Line 2 baking trays with baking paper.

Melt the first measurement (200g) of chocolate and the butter togtether in a bowl over a small simmering pot of water. Set aside.

In the bowl of an electric mixer fitted with a whisk attachment, or in a bowl with a hand beater, place the eggs and sugar. Beat for 5-10 minutes on high until light and fluffy (should almost hold a ribbon shape). Sift over the cocoa and instant coffee and whisk to combine.

Pour ⅓ of the melted chocolate into the egg mixture and mix well, then pour the remaining melted chocolate in and mix again.

Add the vanilla, salt, flour and baking powder and mix gently until just combined. Do not overmix.

Fold in the dark chocolate chunks.

Drop tablespoon of mixture onto the baking trays, leaving space inbetween for spreading. Bake for 8-10 minutes.

Allow to rest on the baking trays for 5-10 minutes and then carefully transfer to a cooling rack.

Place 1 cup of COLD caramel in a bowl and beat with an electric hand beater until light, fluffy and spreadable - about 5 minutes. If the caramel is still warm and runny, it won't beat into a frosting consistency.

Liberally spread the salted caramel frosting on a cookie , then sandwich with another cookie. Repeat with the remaining cookies.