Icings, fillings, creams, decoration and presentation
What this domain tests
This domain tests icings, fillings and creams with their stability, safety and presentation. Expect buttercream, ganache, whipped cream, pastry cream and royal icing, plus crumb coating, piping and finish.
Core rules
- Buttercream is fat and sugar based; it must be smooth and spreadable. Warm buttercream separates or collapses, so cool it briefly and re-whip.
- Ganache is chocolate and cream. Ratio controls texture: 2 parts chocolate to 1 part cream by weight gives a firm filling or truffle; 1:1 gives a softer filling; more cream gives a glaze. Heat cream gently and avoid overheating.
- Whipped cream should be cold and not over-whipped. Stabilise if needed for holding. Pastry cream is cooked starch-thickened custard and must be cooled quickly, covered and refrigerated.
- Royal icing dries hard and suits piping; it is not a cream filling.
- Apply a thin crumb coat, chill, then finish. Keep piping pressure even and place decoration with purpose. Creams containing egg or dairy need strict temperature control.
Worked example
For a firm ganache filling, use 300 g dark chocolate and 150 g cream, a 2:1 ratio. For a softer filling at 1:1, use 300 g chocolate and 300 g cream. For a pourable glaze, use more cream and warm gently. Reason: the chocolate-to-cream ratio changes set and flow, not just flavour.
Traps
Boiling cream into chocolate and causing split ganache; over-whipping cream; leaving pastry cream warm; using royal icing as a dairy filling; decorating a warm cake; applying heavy decoration without support.