Possible Clues:

• Huge flans served up — that's the plan
• Plan to put treasure under layers of rock
• Plan to have stone layers on top
• Plan of nasty master restricting children's game
• Manoeuvre — Ma's target (anag)
• Cunning manoeuvre
• Plan to make great pastry dishes rise
• Ploy grinding one down takes time
• What may deceive you is those layers of precious stone