Chocolate Sandwich Cookies with Vanilla Cream

Beat the wet ingredients. Beat the softened butter, caster sugar, golden syrup, salt and vanilla together for 2 minutes, until creamy and well combined. The golden syrup adds moisture and a touch of chew to what would otherwise be a very dry, cocoa-heavy dough. No need to worry about overbeating here, since there's no egg to toughen.

Bring in the dry ingredients. Add the cocoa, flour and bicarbonate of soda and mix on low speed until the dough looks crumbly at first, then comes together into a stiff, cohesive mass. Only add the milk if the dough genuinely won't hold together, a teaspoon at a time. With no egg in the recipe, this dough bakes up crisp and snappy rather than soft.

Chill the dough. Shape the dough into two flat discs, wrap them, and chill for 30-60 minutes. Chilling makes the dough firm enough to roll thinly without tearing or sticking. This rest also lets the cocoa's flavour settle through the dough.

Heat the oven. Heat the oven to 160°C (140°C fan) for at least 20 minutes, with a shelf in the middle. The relatively gentle temperature helps the thin wafers dry out evenly without the edges scorching before the centres set. Line two large metal trays with baking paper ready for the cut rounds.

Roll and cut. Roll the dough between sheets of baking paper to about 3 mm thick, then cut into rounds with a 5 cm cutter. Re-roll the scraps once to use up the dough, and space the rounds 2 cm apart on the lined trays. Rolling between paper keeps this sticky, cocoa-dark dough from picking up extra flour, which can dry the wafers out.

Bake the wafers. Bake for 13-15 minutes, until the wafers feel dry and firm at the edges and look slightly darker right at the rim. Because the dough is already dark with cocoa, colour alone is hard to read here, so trust the firm edge as your main cue. The centres will still feel a touch soft when they come out, but that firms up as they cool.

Cool completely. Leave the wafers on the tray for 10 minutes, then transfer to a wire rack to cool fully and go properly crisp. Don't try to sandwich them while they're still warm, as the filling will simply melt and slide off. They need to be completely cold and crisp before filling.

Make the vanilla cream. Beat the soft butter, icing sugar, vanilla and salt together for 3 minutes until stiff and smooth, adding milk a few drops at a time if needed to loosen it. Beating this long whips enough air into the filling to keep it light rather than dense and greasy. The finished cream should hold its shape on a spoon.

Fill and rest. Pipe or spoon a heaped teaspoon of the vanilla cream onto the flat side of half the wafers, then top with the remaining wafers and press together gently. Rest the sandwiches for 30 minutes to let the filling firm up before serving. Makes about 22 sandwiches.